Hello i know some of you have experienced the same crashes and black screen as i did
There is a fix for this at least for the black screens 10 minutes in the game didn't have any crash at all.

1: Downgrade your game to v1.2.10
2:Make sure you download Harmony, Europe map by Lemmy, Empires of Europe 1100 and BannerColorPersistance v1.2.0
3: Load the mods as follows A: Harmony.
B: All native mods.
C: All other mods if you've other mods.
D:Europe Map
E: EoE 1100
F: BannerColorPersistance

https://www.nexusmods.com/mountandblade2bannerlord/mods/2637?tab=files&%3Bfile_id=33419 (Download the 1.2.0 beta version)

Now for the crashes if you want your game a little better optimised you can try increasing VRAM and lowering a little bit the graphics so your GPU can handle it better and not overload.

For Windows 10/11
1: Open Files
2: Go to your system
3: Right click and select Preferences
4: Click Advanced Settings for Advanced Users
5: Advanced settings
6:Performances
7: Visual Effects set it for performance mode
8: Go for advanced users and then Virtual Memory
Change your VRAM search on Google how much you need to change it to for your system (Sorry i don't know)

And you should be okay to start playing
Enjoy! That's how i fixed mine.