I have a gulikit king kong pro 2 (I think I got the name right). Been using it about a year now, works good on linux (Nobara). Has various modes for different consoles and phones and hall effect sensor sticks (which wont have stick drift) which was the motivation for trying it, along with the lower price compared to the official Xbox controller. Came with a nice hard case and rechargeable lithium too.

Been pleasantly surprised so far.

Yep sounds like firewall issue to me. Allow the ports eric mentioned in his comment thru firewall and it should work

np, glad it helped

One sticky point that took me a bit to clue in to was you need to login to an x11 session not the default Wayland. Unless sunshine has been updated to support wayland, this was about Feb I discovered that.

To change just log out and select x11 in bottom left corner of the login screen. Dont forget to switch back next time if you arent using sunshine

Having tried both popOS and manjaro I’d urge you to skip my trail and error and check out Nobara from the get go. Always found little naggling issues until I found Nobara