Foreward: I'm the guy who has been trying to clean up and fix some of the machine translation of the English patch. As a result, I've had to poke around in a lot of the mod's raw code, so probably understand it better than most Anglophones. I thought I'd throw a guide together with my knowledge. It's incomplete and missing some stuff, but hopefully will still be helpful.

WARNING: When you start the game, you'll get an Azur Lane tutorial lady speaking in Chinese. Besides showing you list of features (you can see this later by opening the diplomacy window to "Central Office"), she'll offer you a three choices. Green (turn tutorial pop-ups on), yellow (politely decline), and red (rudely decline). Note that selecting the red option causes her to destroy your entire home system. Since it's at the start of the game and you probably only have a single colony, this usually means an instant game over. So if you find yourself instantly losing on game start, it's not a bug, it's only the author's sense of humor.

"Central Office" is the interaction menu for most of the mod's content. It can be accessed through the diplomacy menu, similar to enclaves.

This is the Chinese-speaking character accessible via the central office. I just call her Tutorial Lady. Besides providing poorly-translated explanations of various game content, she also has a few hidden features, if you have sufficient favour points (earned by completing events, offering her gifts of money, and using the Azur Lane oath feature on Azur Lane leaders). Like the Shroud you will be able to ask her for a boon every few years, which at first are just packages of resources. At very high favour you will be able to request unique admirals, and unlock the final tier of Azur Lane ship technology, assuming you have fully research all the previous tiers of Azur Lane ship technology.

This mod doesn't follow the normal path of "research stuff to progress" that most mods follow. Instead, tiers of technology are gated behind ascension perks, so plan accordingly. To unlock the next tier of ascension perk you usually must research all Azur Lane ship equipment for that tier; if you're the sort of player who researches only one weapon type to min-max research progress, you may find yourself never able to progress to the next tier of weapons. You must research all weapon types! This includes vanilla weapon types.

Most of the ascension perks unlock in a simple linear order, with a few exceptions:

Advanced Military Plan: This perk is strictly limited to stuff involving planetary bombardment and invasion. It unlocks extremely powerful armies, but may be considered entirely useless if you never intend to invade planets and instead rely on colossuses and the like.

Mind System Overclocking: This unlocks a powerful species trait and I believe is used to also unlock the big Mind Network event chain, which will be explained in another section of the guide.

The God of Mould Planet: From the description and direct effects this looks like it's just the Azur Lane's version of the terraforming unlock perks since it mentions nothing other than terraforming. However, it is actually part of the path to unlock higher tiers of technology, so ignoring it in favor of combat-related perks may actually hurt you in the long term by blocking access to higher tier ship equipment.

Milky Way Terminal Weapon: WARNING: This will unite the galaxy against you. It's pretty much similar to Gigastructural Engineer's Nicoll-Dyson Beam in that it unlocks a massively threatening superweapon that causes the entire galaxy to turn against you.

Special Note: After unlocking the majority of the perks (except Milky Way Terminal Weapon), you may find progression halted. It's not explained anywhere, but you must have sufficient favour with the Tutorial Lady and then request she grant you the final tier of technology. This is not to be confused with the other request you can make of her for technological assistance, which just provides a country modifier to boost research speed. That's a different thing.

Mind Cube: The lower-tier strategic resource. Looks like a blue cube. Can be obtained via a branch office building, a factory building, or produced in small amounts by Azur Lane administration and bishop/pope rulers.

Starship Technology Box: The higher-tier strategic resource. Looks like a red cube. Can be obtained via branch office buildings or a factory building.

Red Diamonds: May also be called gems. This is a special currency that can be redeemed in the Central Office for various amounts resources. Obviously free resources are an unfair advantage, so you probably will never spend any if you want to play a "fair" game at reasonable difficulty. It's also used in tiny amounts in super-overpowered, cheat-tier starship equipment, or the highest tier building constructions. Note that since these aforementioned spending options are both late-game content, you'll be sitting on a mountain of red diamonds by the time you need to spend them, so don't feel you have to horde or ration them in anticipation for late-game.

It's not explicitly mentioned anywhere in the game text, but certain ethics and their respective civics (most Azur civics are restricted to those that have a specific ethic) have hidden effects that aren't mentioned in the tooltip. I will list these hidden effects (but not their already-stated-in-the-tooltip effects) below. All the job output bonuses mentioned below only apply to Azur-specific jobs from Azur Lane buildings, and not to "normal" jobs in vanilla Stellaris jobs, unless explicitly mentioned otherwise.

Azur Lane Church. Spiritualists only. +50% base yield for cube priests and cube bishops. Cube priests are like normal priests, but also provide food, energy, and minerals on top of the normal unity output.

Azur Supreme Leader Succession System. Non-Egalitarian only. Large boost to most Azur Lane ruler-strata jobs; e.g., provides +100 admin cap to Popes, +10 Soc Research to Bishops, +7 Unity to Generals, +4 Unity to Bureaucrats

Azur Lane People's Assembly System. Egalitarians only. Provides 1-2 extra unity all Azur Lane jobs. +5% country unity from Central Secretary.

Azur Lane Prosperity Guild. Militarists only. Provides +20% base yield for raw resource gatherers. +1 red diamond per month from Central Secretary.

Azur Lane Experts Union. Provides +15-33% more base yield for alloys/goods/refinery specialists. Provides +3 science to other types of specialists. +5% specialist yield from Central Secretary.

Azur Lane National Security Agency. Soldiers provide additional stability. -10% War Exhaustion from Central Secretary.

Azur Lane Embassy. Extra Envoy from Central Secratary.

Azur Lane National Academy of Mental Sciences. +25% leader XP gain, +1 leader level cap from Central Secretary.

All ethics-specific buildings require technologies are gated behind the presence or absence of certain ethics, so this section combines both building and research restrictions.

Militarists: Multiple researches to improve ship hulls. Unlocks Starship Technology Box Megafactory.

Pacifist: +5% to raw resource gathering, +3 districts per colony

Xenophile: Unlocks ability to give aliens a bonus trait, extra envoys, extra trust cap

Xenophobe: Reduced influence costs for starbases and claims, doomsday bombardment stance

Authoritarian: Unlocks Executive Fortress building (large bonuses to ethics attraction, stability, crime reduction, and job upkeep cost reduction). Planetary decision for +40% yield and upkeep for ruler strata jobs.

Egalitarian: +25% faction influence. (If also NOT spiritualist) Unlocks Intelligence Archive (gives bonus to researchers and specialist outputs). Unlocks Star Net Council, a planetary decision that grants 1 StarNet Speaker job per 50 pops (each of which grants +1 district, effectively leading to uncapped planet size growth)

Materialist: Improves most aspects of espionage, and various robot bonuses.

Spiritualists: Unlocks Oracle (has cube priests jobs that also provide food, minerals, and energy on top of the normal unity normal priests have). Unlocks planetary decision to declare one planet a holy land, doubling base yields of all cube priests and bishops, +20% yield to all priest-type jobs (even vanilla ones), and one cube priest job per ten pops. Yes, this is as overpowered as it sounds; cube priests alone can meet all food and mineral needs of your empire if used properly.

This is a huge part of the mod content, so this part may be a bit long.

This project has various names depending on the stage. But basically they allow the resurrection of dead leaders, the menu for which is available via the Central Office menu under R&D department. In addition, there are secondary effects depending on if you chose the spiritualist or materialist route.

Spiritualists
This will allow you to basically harvest alien souls for planetary bonuses. It requires you have the Mind Personality Matrix built, then enact the Mental Personality Matrix Start to begin the program. Every month a few alien pops on that colony will automatically killed and turned into points. At certain amounts of points larger and larger resource output bonuses will be granted to the colony, in addition to a national research speed modifier.

You can eventually build Mind Subnet Access Points, which are like weaker versions of the original Mind Personality Matrix: they only get half the bonus of the original. You can also extend the alien soul harvesting ability to other worlds using the Mind Marking Decree planetary decision (note that there is a similar decision which lets you toggle this function off on a given colony, if so desired). Note that all Mind Network buildings share access the same pool of points; sacrifices in one colony will add to the scores of all other colonies. Scores can be viewed by examining the tooltip of the original Mind Personality Matrix building.

Materialists
Instead of killing alien pops, they instead get the ability to turn alien pops into synthetics of your own design. Kind of like the synthetic ascension project, but automatic and only applying to non-shipgirl races.

You will eventually get an event and special project for something called the Galaxy Mindnet. This will eventually provide a massively powerful country modifier when complete: +50% naval cap and admin cap, +25% starbase cap, +50% megastructure build speed, +3 megastructure build cap, +15% megastructure output, +200 fleet command limit. However, this comes at a cost. Much like unlocking another powerful advantage, jump drive technology, researching this project will trigger an inevitable hostile crisis.

Eventually you'll get a chain of events about stuff going wrong or bugs in the system. Ignoring them speeds up the crisis' time until arrival. Trying to fix it delays the crisis temporarily. Choosing to shut off the system (via the event choice) is the only way to stop the crisis, but removes any bonuses you received. If you haven't shut off the system, eventually a barren planet within your borders will transform into an evil city planet. And I know what you're thinking, but no: conquering the system, invading, or blowing up the planet has no effect on the crisis, so don't bother.

Crisis Effects
You know that massive bonus country modifier you got from the Mindnet? That gets negated. You may also get a bunch of negative modifiers, though I'm not exactly sure what triggers them. (Some may get bugged and stick around after the crisis, so you may need to use console or save editing for force-remove them). The crisis will wipe out the population of a planet upon capturing it, much like the Unbidden. It will also periodically spawn huge invading armimes on five random colonies owned by you, so you may wish to pre-emptively garrison your colonies with large armies before the crisis kicks off. And like every other late-game crisises, it spawns fleets that go off and attack everyone nearby at random.

As for the crisis ships: The crisis gets all your technologies. This may mean the rest of the galaxy is going to get purged very quickly if you happen to be far more technologically advanced than the galactic average. Which may be a good or bad thing depending on how you play. It also means you can only beat the crisis through sheer volume of numbers, since any technology advantage you have is now nullified.

Beating the Crisis
The crisis periodically spawns fleets of two types. Generic fleets which randomly attack stuff like other crisis fleets, and fleets named after seven deadly sins: lust, greed, wrath, etc. These themed fleets all have unique aura effect giving them extremely powerful, specialised stat boosts: Some have incredible 200% evasion, some will regen HP faster than a decent fleet can damage them, some have insanely high damage, etc. Talk to the tutorial lady in the central office for exact details on which sins have which auras.

Anyway, you have to kill seven of these "sinful" fleets to unlock the final boss. Which seven does not matter; you can kill multiple of one sin and none of another sin if you so desire. After the seventh dies, the boss fleet will spawn. Knock it out to defeat the crisis.

You'll get a random event that might be poorly translated as "Ultra-Generation Titan Soldier" or something. What it should say, if I haven't fixed the translation is that: "Colossus ships kind of suck, being weakly armed, slow and fragile. What if we stick a bunch of weapons and armour on it?" And this special project will unlock a hull module with a lot more weapon and armour slots.