It’s best to manually edit the configs for each system to set up the key
input_hold_fast_forward_btn = 9
input_exit_emulator_btn = 0
input_rewind_btn = 8
input_pause_toggle_btn = 3
input_reset_btn = 12
These entries will be preferred than the entries in /opt/retropie/configs/all/retroarch.cfg
Or you can set in RGUI the option “save on exit” to true.
I think this option can be found in settings -> Generall Settings
.. I don’t know the Path of these option exactly now.
But I do not recommend this because the whole config would be overwritten with the actual retroarch settings.