Here is an instruction to start openwrt as a custom WSL2 distro.
I didn't start it as a gateway in my local because I don't have windows 11 installed, and you know the poor network mode in windows 10 and wsl2.
Found a way to set WSL's network mode to bridged here and have successfully configured it as a gateway in my local.
But anyway, I think it should work under windows 11 and wsl2, since you can config it as bridged mode.
Have fun!
you can download from the official site