I’ve found pigs (i.e., not the mod’s wild boars) spawning in the enclosed areas in villages where pigs normally spawn. Unclear if you intended for this to happen, but it does allow one to circumvent having to domesticate wild boars or the other mobs.

It is not intended, but I dont know how to remove this mobs, not spawned but added as part of world generation

Fixed in 1.16, in 1.15 not possible to fix