Gamepass is just Windows Store with a slightly cooler name. So if there’s a Window’s Store trainer (ie - State of Decay 2 (Windows Store) Cheats and Trainer for Windows Store) then it’ll work with your Gamepass subscription games.
At WeMod trainers are made for particular game versions if players vote for it enough times (click here for more information). However, the trouble is that Windows Store (aka “Gamepass”) is not a very popular platform with the wider gaming community, so ultimately yes voting can tend to take longer compared to, say, Steam or Uplay games.