For those wondering... I have found a few with the stuff i was looking for. I forgot this post for so long, but i'll look through my games folder, and probably add some more here:
So far i found:
Secret Horse Files 3 (Big dildos, but it's furry... so yea...)
Project Myriam (bestiality, fucking a horse)
Sex and fantasy (Centaur fuck game)
What i've found is, that usually the hardcore anal is directly linked with bestiality, so it might not be for everyone...
I did start trying to create my own game lately, but it'll be a while before that has any sort of hardcore anal. Gotta prepare the girls first...