There's already a big thread in regards to Fortnite. It's important to note that it's not the Xim being detected, but keyboard input. Epic is splitting the console userbase into separate controller and m/kb lobbies.
This has been added to Fortnite to stop users from entering a game with a controller, then swapping to kb. It has nothing to do with Xim, other than Xim supporting keyboards.
It also affects licenced m/kb adapters on PS4, like the Hori Tac Pro. That's going to cause Epic some problems with Sony, so there'll be more on this story to come.
It's being worked on right now for Apex. There'll be a solution and it won't take long.
