>>9537
Some of that is in the mod, though not as indepth as you'd get from something dedicated specifically to interspecies relations. For example going by each point:
>marrying your son off to the neighbor monster kingdom for favors or to avoid war
Different species can't have royal marriages, even though there's a lot of intermarrying and reproduction in the lore if your king is one species you can only marry with another kingdom of the same species.
>monster integration policies bringing benefits and drawbacks
This actually does play a role, each species brings certain advantages and disadvantages to each province they're in depending on how large their population in that province is and how well they're integrated into your society.
>welcoming the monsters gives you very strong army
In the mod only your primary species makes up your army, though with certain nations you can get permanent modifiers for missions that involve having other species integrated.
>human purity terrorist cells forming
Funnily enough it was actually the opposite for that kingdom of Gelkalis, it was Harpy supremacists who didn't want to integrate and launched a guerilla war for a few decades.
>long-term demographics planning
I wish that was more of a thing but it's not, minority populations can grow or shrink, I don't know if it's based on anything or just random, and you can accept refugees from other nations that expel populations but your primary species will always be primary.
>manage relationships with pure human nations, as you get comfier with monsters human supremacists start treating you with distrust
The only way this sort of gets expressed is at the beginning of the game there's the races considered civilized, like humans elves and dwarves ect. and the uncivilized ones like orcs goblins and harpies ect. and the two groups hate each other, but as the game goes on the monster races can work to be viewed as equal nations, each individual nation still decides on the groups it wants to integrate or oppress in their own borders but relations between nations improves.