Velvet
Hotkey + START does not work for you to quit?
What kind of controller do you use?
In Batocera 5.22 there is unfortunately only standalone Citra as emulator and you can not configure the emulator.
In previous Versions (5.21 for example) there is also Libretro Citra, where you can enter the RetroArch Quick Menu to configure some settings by pressing Hotkey + B while in game.