Im using the gamepass version too, its not difficult!
Just choose the ""gamelaunchhelper.exe" instead of the game.exe file for reshade inside the game folder and it works just as easy.
yeah, i realized that last night when i was trying to get the game to launch via steam so i could add the bypass parameter to the launch file, and steam would only let me add the game launcher file. I was able to launch reshade with it but it found no patches. I didnt realize until afterwards that i had added the reshade only to the main game exe.
Honestly, i despise the xbox app. I couldnt even access my save file for Marvel's Avengers and move it to the Steam version because microsoft dont believe in storing save files in the Documents Folder like everyone else. Never had any problems with Uplay or the EA app and everyone hates those.