i cant get mods and cheats in mafia 2 because of family sharing but i can get mods at sekiro also its family sharing tho idk why but mafia 2 doesnt works
Hello and welcome. 
Make sure you’re using the correct trainer for the version of the game you have.
FYI, if you had Mafia II prior to, I believe, 2020, purchased legitimately from Steam, then it was upgraded for free to the Definitive Edition.