Hi folks
this is do-able quite easily now -- certainly as far as non GUI desktops are concerned -- I'm still playing around with seeing if a decent desktop GUI works too. Some GUI programs work OK -- needs more testing though.

Here is a post I did on the W11 Forum for installing ArchLinux in the WSL. The main trick is to create a tar image of your distro and import into the WSL.

Run Custom Linux Distro on WSL e.g arch Linux - CLI though | Windows 11 Forum.

have fun

Cheers
jimbo