xpadneo VS GIMX

In the other distros I've tried (ubuntu / pop os) I usually solve the problem by installing xpadneo using the official method that can be found here. But this doesn't seem to be working in this case. I've already tried using gnome bluetooth settings, blueman and bluetoothctl.

That was more than a year ago though and it seems some people are working on linux drivers. xpadneo is probably a good starting point: https://github.com/atar-axis/xpadneo

If that doesn't work either, I would try making an issue on their github and asking there: https://github.com/atar-axis/xpadneo/issues

2) install https://github.com/atar-axis/xpadneo

This very same controller has worked on this very same physical computer in the past, but under Ubuntu using the xpadneo driver (https://github.com/atar-axis/xpadneo/). One day, for no reason as near as I can tell, it simply stopped working and showed the exact same symptoms as above (controller works for phone, not for PC, doesn't show up in bluetooth list. Other bluetooth devices work fine with the PC). This triggered my distro-hop to Endeavour just to discover the exact same issue.

You can try this custom mapping from xpadneo: https://github.com/atar-axis/xpadneo/blob/master/docs/SDL.md

A second option would be to ask GIMX developers to make a snap package, if possible. Converting .deb packages to snap packages is supposedly easy and without problems.