FIX FOR DISCONNECTION IN RIVALS/RUSH PC
I found a fix guys. This is what worked for me so don't know if it's gonna work for everybody, also I play directly from the EA App.
First of all I deleted the EA FC 26 folder that it's on this url: C:\Users\[your user]\AppData\Local
There u search for the folder named "EA SPORTS FC 26" and delete it all the folder.
Then go to the EA APP then to your library and clic on the three dots on the game and then clic on repair.
Wait until the game is fully repared, open the game and play a match to see if worked.
I don't know if the folder changes location if you got the game on Steam or Epic but I guess you can search for it.
Also if you don't find the AppData folder is because is hidden so you must have activated the show hidden elements option in the windows explorer.
Hope this solve it for you too.
P.S. You don't have to disable cross-play. It works totally fine with cross-play activated
