@substring I confirm, with GFE 3.13.1.30 it work, I can view my desktop, play games and videos from the web or VLC.
I used the commands :
cd /recalbox/scripts/moonlight
./Moonlight.sh pair <MY_IP>
./Moonlight.sh init <MY_IP>
reboot
Sometimes, the application or games won't launch but I can view my desktop and I can launch the application or the game, it's not a problem for me. The sound work fine.
I need only to stop the stream with GFE from Shield - GameStream option to get back in the menu of the Recalbox.