I narrowed down the problem to ButterLib 2.6.2, the 1.0.3.9860 stealth update broke it, and i can't use any dependent mods, like Diplomacy, MCM, Dismemberment Plus. I have to wait until ButterLib fix.
I tried to roll back to 1.0.2, i fully reinstalled the game, and redownloaded all mods for it, but it still crashed on startup.
EDIT:
I get it now, the 1.0.2.8368 stealth update also broke the older ButterLib 2.6.1, that's why rollback to 1.0.2 didn't work.
TW devs are really pro in breaking the modded games, kudos for them