Microsoft published a brief FAQs on the app compatibility of the upcoming Xbox Series X and Xbox Series S consoles.
App Compatibility for Xbox Series X and Xbox Series S Consoles
UWP applications (both apps and games) are a pivotal part of the Xbox experience. As we near the launch of the new console generation, we want to address some common questions regarding app and game development on the new Xbox family of consoles. If you have been developing for the Xbox One X using UWP and leveraging the Dev Mode Activation App, the same features will be supported on the Xbox Series X and Xbox Series S. Please refer to the following FAQs for further guidance.
App Compatibility for Xbox Series X and Xbox Series S Consoles