Hi, i "solved" this in the spanish forum.
I found this video How to Fix 5 FPS Bug in EA FC 26 – 100% Working (2026) , and work perfectly to me and my friends.
The problem is that this need a monitor with 4k resolution, do not works on another configuration, you have to use the same steps that the video.
The problem occurs every time I open the game, sometimes in the Menu, or in a match, or in the second time, but once I follow the steps when the problem occurs, it doesn't happen again until I close the game and reopen it later.
I would add that january update did not solve anything; it is the same or worse.