I found a solution for my own setup. May be it will be useful for you.
1. I have a ps3 joystick with bluetooth capacity. I'm using scptools and it recgonize as xbox joystick.
2. I can play forza horizon just fine with this joystick.
3. But the SW Battlefront II is giving me very jerky control over an oversensitive crosshair.
4. took me forever to figure this out. I found many posts saying you need to remove origin overlay. But that's just useless for me for whatever reason.
5. I figure out how to do this today after another long trial and error.
6. you just need to go to key binding. and remove mouse x/y from look up/down/left/right and joystick will control ship instead of crosshair. You remove the mouse control using x icon near the look control. using esc key will not unbind the keys. This removes mouse control entirely. But joystick works much better than mouse control.
7. after you do this, if you are using steam version, you can set right joystick to crosspad with analog option. this analog control allow you to specify how fast each stroke is on the arrow keys.
8. you can also experiment with the in game joystick sensitivity. just notice ship control is called starship, not vehicle or on foot.
this should resolve the issue with joystick not working if it is too sensitive.