As far as I remember you don't need to disable ERTM anymore, I haven't done it and my series x controller works fine.
Furthermore you should ssh into your device and add a udev rule.
This is what I have done:
nano /storage/.config/udev.rules.d/99-gamepad.rules and add
CodeSUBSYSTEM=="input", ATTRS{name}=="Xbox Wireless Controller", KERNEL=="event*", MODE="0666", ENV{LIBINPUT_IGNORE_DEVICE}="1" SUBSYSTEM=="input", ATTRS{name}=="Xbox Wireless Controller", KERNEL=="event*", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"
, you should put that into a single line. Should work.
Thanks.
Now i can configure the Controller
But without the Menü Button...