I use 2 Xin-Mo Xin-Mo USB Controllers

My button 8 for exit is off the player 1 USB controller.

If I copy my retroarch.cfg from my 2.6 retropie image (attached below) and put it into pi@retropie /opt/retropie/configs/megadrive $ my buttons are all good and the button 8 exits the emulator perfectly.

As you say its a messy way of doing it why I don’t like, would be nice to know how to get this to work the cleaner way.