They’ll look for digitised movement like Epic Games did.
OBsIV implemented SAB so that keyboard movement looks less digital and is harder to detect, but even then it can’t ever appear as completely analogue - a straight line will always be straight, even if it’s only straight for a few micrometers.
If Respawn kick players using digitised input devices then they’ll kick XIM players. But they’ll also kick players using Microsoft and Sony-licenced products and those used by disabled players. Until such time as they work out how to do the former without doing the latter, they’ll take no action. And as only a tiny percentage of players are using a XIM (OBsIV recons the number of XIMmers on Fortnite is significantly less that 1%) they’re extremely unlikely to use their limited resources to detect it (they need to sort out their netcode and hit detection issues, first!).
As I said, the devs are just appeasing the vocal XIM-haters. It’s just hot air. If Epic Games couldn’t do it with the all-conquering FN, poor little Respawn have a snowball’s chance in hell.
(But just incase, OBsIV always has a plan!
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