[HideousKojima]

Yes:

https://xemu.app/

https://xqemu.com/

Are both original Xbox emulators built off of QEMU (Xemu is a fork of XQEMU). I've only used Xemu, but performance was pretty good for the games I tried on it (it doesn't have a way to upscale rendering yet though).

[MegaDeKay]

Good news! Upscaling is in work but buggy right now.

https://github.com/mborgerson/xemu/tree/feat/surf-scale