Regarding my bluetooth issue with a DualShock controller, it has been reported in bluez issue tracker here. LE 12 has the same version (5.73) as the one reported having this problem. Latest bluez version is 7.75 but it is not clear to me if the fix is included. There is a workaround mentioned here, but I'm not sure how to apply it on LE. Maybe the best solution is to downgrade bluez.
See https://github.com/LibreELEC/LibreELEC.tv/pull/8820 - I’m building an image for you to test.