Yes it is compatible. It overrides some lines of the same YAML. You must put this at the bottom of the load order.

Is this still compatible with 5X and UCP? Do these mods override the same YAML?

PERFECT.

Farmers do not live in harmony with nature. They transform the environment to suit agricultural needs, killing everything in the process.
An apothecary who picks what nature grows to brew certain medicines at certain times of the year and has knowledge of pharmacology, flora and fauna is a scientist who lives in harmony with nature.

I'm excited to introduce a new mod, which make changes to balance for a slightly more realistic usage of special in game.
Try "Realistic Specials" https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=2348837077

Dear LRG_NL.
If your question is still relevant, еhis mod has 5 levels of relationship development. Buildings like spaceport and outpost help to capture priority over another player, but don't increase the relationship level.

what are the levels of development of relations? are it the investements, which if it is the case then 5x has 9 lvl, or are it the buildings that the system contains, like a space port and outpost

1. MinorCivClasses.yaml, RaceTypes.yaml
2. Yes

2 quastions. 1: which YAML did you alter, and 2: is it compatible witch 5x and DSMP

Nice mod; I've done something quite similar in my own local mod. Minor leader lore text may suggest some other classes - you may want to check them out. The game is messy with the minor civ assets- they are all mixed up so it's a bit of a puzzle and a matter of choice. Not sure if you did but you can change the city lights too (I believe they're all set to Alkari iirc).

for example:

Akirian Highness = Research: "The soft, jelly like bodies of the Akirian have made them horrifically unsuited for combat, so they have collectively turned their interests towards science and academia."

Eldritch Scribe = Research: "Part scavenger and part scribe, the Eldritch know secrets of the universe that they should never have access to knowing."

Glis Janitor = Workers: "Trevor, a bumbling sack of idiocy with no arms or legs, is the best ambassador the Glis could come up with. He pushes a broom around pretty effectively and has only broken three maintenance tools this week."