Ok, haven´t had much luck yet, of course the delivered Pad works and all DB9 Joysticks so far ....
A500 Mini Pad (wired) -> won´t work
PS4 Pad (wired) -> works (BT not tested)
Xbox Series S/X Pad (wired and BT) -> won´t work (is shown but will not pair on BT)
Logitech Gamepad F310 -> works -> needs to be in "DirectInput" mode
Speedlink Competition Pro USB -> works
Hyperkin Scout Premium USB -> works
8BitDo M30 (BT) -> works (wired not tested, should work too)
Retrobit Mega Drive 6/8 button Arcade Pad with USB -> works
Gamesir Nova Lite -> works
DB9 :
Competition Pro -> works
Quickshot II -> works
Atari Joystick (Clone) -> works