What i do :
- Install FC and Mod everything i want
- Backup this whole Folder (name it to EA SPORTS FC 25 Modded)
- then when a TU Update comes, i let it update
- when done, just rename the updated folder to (EA SPORTS FC 25 TU xy)
- rename the EA SPORTS FC 25 Modded to EA SPORTS FC 25
- play as usual
when i am done with playing i do it all reverse :
- rename EA SPORTS FC 25 again to EA SPORTS FC 25 Modded
- rename EA SPORTS FC 25 TU xy to EA SPORTS FC 25
in this case you have always your modded Folder saved
For FC 24 there was a thing that you can revert the TU update with xy files, but i dont know this version