You can install the new Xbox Full screen experience mode for Windows on handhelds but whether it will work is another question entirely

Microsoft's "Full screen experience" mode for handheld gaming PCs shouldn't officially be usable yet, but it turns out you ...

New Windows 11 update lets you try Xbox Ally fullscreen mode on other handhelds

You can now try the new fullscreen handheld mode on a Windows 11 handheld gaming PC by installing update 25H2, available to ...
TweakTown

Xbox app full screen experience leaked, can run on handheld PCs with Windows 11 25H2

The new-and-improved Xbox app for handhelds has been leaked through builds of the OS, and can run on any handheld gaming PC running Windows 11 25H2.
XboxEra on MSN

Xbox's 'Handheld Mode' Available to install on any Current Windows Handheld

As the teams at Xbox and ASUS prepare for the launch of the upcoming ROG Xbox Ally and Xbox Ally X in October, the Windows ...
IGN

Microsoft to Make Windows on Handheld Gaming PCs More Like Xbox This Year

Microsoft is looking to improve its Windows operating system on handheld PCs such as the Asus ROG Ally X and Lenovo Legion Go by making the software more like an Xbox console. Microsoft vice president ...