The file is on protondb? Also hows the performance? Does it run well on the deck?

Wait you got battlefront 2015 working?

Battlefield 1,4,5 works on steam deck but as of the last update All of them has had a little bit of performance issues, Link the EA account you want to use to your steam account, you gotta do this all via desktop If the game was bought via steam then this should be easy but if you bought them via EA then you’ll just have to put the game as a non steam so you’ll be able to play it via game mode