@Nachtgarm Yep, its functional in this way 😉
A little pain to set... but if you use the main emulator as source (the plataform which has the majority of the games) the process will not take that long.
The Street Fight 'series' for example:
The M.A.M.E. is the main platform - i just added the FBA LibRetro (for CPS3 games) and PSX (for some Vs games).

i changed some music and backgrounds, for example music of snes, i dont like start with zelda musc (for example) i feel it too noisy... so this is my custom list:
PlayStation
PC Engine
PC Engine CD
Super Grafx
Scumm VM
FBA Libreretro
MAME
NEOGEO
Atari 2600
Atari 7800
Atari Lynx
NEOGEO Pocket
WonderSwan
WonderSwan Color
Doom
Vectrex
Cave Story
MSX
MSX2+
ODISSEY ²
Super Nintendo
Nintendo
Nintendo 64
GameBoy Advance
GameBoy Color
Gameboy
Nintendo Family
Virtual Boy
Game & Watch
Sega Genesis
Sega CD
Sega Megadrive x32
Sega MasterSystem
Game Gear
Sega SG-1000

brother if you like some one change, take it, be free, i will upload a video soon (may be this week), i do not know how to take screenshots of that, may be i need a HDMI recorder case? how do you do? also the sound part is very very important in this case.