I honestly have never heard of xcloud before now so I can’t speak on it. I do however have experience with Fortnite using Amazon Luna (free with Amazon prime) and it works surprisingly well even with my crappy Internet and connection. It looks really good and the latency was surprisingly good too, unless I’m at the farthest point from the router then it’ll freeze occasionally.

I’m not sure what you found difficult about this type of game with the steam deck controls but it works just like a regular controller by default.