I'm encountering the same issue.
When I try to build and run my app in Visual Studio, I get the following error:
"Could not find SDK 'WindowsMobile, Version=10.0.26100.0'."
I'm developing for HoloLens 2 using Unity 2022.3.25f1.
Everything was working fine before I updated Visual Studio, this problem started right after the update.
Is there a known fix for this?