Hello wiki page : https://github.com/recalbox/recalbox-os/wiki/recalbox.conf-(EN) this exemple :
## You can override the global configuration here
## Here is the snes example
;snes.videomode=CEA 4 HDMI
;snes.core=snes9x_next
;snes.shaders=/recalbox/share/shaders/shaders_glsl/mysnesshader.gplsp
;snes.ratio=16/9
;snes.smooth=0
;snes.rewind=1
;snes.autosave=0
;snes.emulator=libretro
## If you do not want recalboxOS to generate the c
onfiguration for the emulator :
;snes.configfile=/path/to/my/configfile.cfg
name of system : Available libretro cores :
snes n64 gb/gbc gba virtualboy megadrive mastersystem gamegear sega32x segacd sg1000 neogeo mame fbalibretro ngp gw vectrex lynx lutro wswan pcengine atari2600 atari7800 msx prboom psx cavestory