Same problem here.

You can add descriptor files yourself in
Documents -> Paradox Interactive -> Europa Universalis IV -> mod
(you can do it in the mod file itself but I just prefer it this way)
create a text file on note pad and save it under any name and drop down selected to save as all file extensions and name it .mod at the end

format is always:

version="1.0"
picture="thumbnail.png"
tags={
"Graphics"
"Map"
}
name="Anbennar"
replace_path="common/bookmarks"
replace_path="common/province_names"
replace_path="common/government_names"
replace_path="common/disasters"
replace_path="common/rebel_types"
replace_path="common/countries"
replace_path="common/mercenary_companies"
replace_path="events"
replace_path="missions"
replace_path="decisions"
replace_path="history/diplomacy"
replace_path="history/countries"
replace_path="history/wars"
replace_path="history/provinces"
replace_path="gfx/loadingscreens"
supported_version="1.30.*.*"
path="C:/Program Files (x86)/Steam/steamapps/workshop/content/236850/1385440355"
remote_file_id="1385440355"

This is an example of my anbennar descriptor file, the supported version and pathfiles are really the only important things here, the rest are just ways for you to differentiate what the mod is.
the path file id numbers are always at the end of the workshop link and you want the path to stop at the main folder, so 1385440355 can be seen as the entirety of the anbennar mod, you want the path to be that, not any folders inside of that, if you open a workshop link in new tab by middle mouse button clicking on a mod, it will open with link shown at the top, most mods dont need all those "replace_path" files but this is a full conversion so those are necessary here
if you want to make a mod playable on a newer or older version of the game all you do is change the supported_version to whatever version you want it on, the asterisks could be seen as a symbol meaning "any number"