@mauline Thanks for your reply and willingness to help.
I did try pairing in android and switch mode. I also changed the line you suggested. But to no avail, ES recognizes the controller on the list of bt devices (correctly, with the correct 8bitdo Sn30Pro and everything) but stays on "In progress..." for a long time and then "Unable to pair controller".
I've tried other bluetooth dongles and also the internal bluetooth. Nothing.
This happens since version 6.1.1. I repeat, version 6.10 works FINE (on the same system, same bt dongle, same board, same everything). Tried the "pair from command line" on 6.1.1 and didnt work, so it will probably not work now again.
I'm stuck on version 6.1.0 only because of this controller problem and it's frustrating...