I got it, you can close the topic.

Consegui resolver, pode fechar o topico.

I've seen systems working with collections of games in the same folder, there are several on YouTube

I'm having trouble creating a game collection, I do all the configuration of the new system on es_systems.
Appear the games, menus and theme perfectly, but the games do not enter, but in their emulators they work normally, someone knows how to solve this, I used as base the Snes line.

<system>
<fullname>Mega Man - Collection</fullname>
<name>mmc</name>
<path>/recalbox/share/roms/mmc</path>
<extension>.smc .sfc .SMC .SFC .zip .ZIP .mgd .MGD</extension>
<command>python /usr/lib/python2.7/site-packages/configgen/emulatorlauncher.pyc %CONTROLLERSCONFIG% -system %SYSTEM% -rom %ROM% -emulator %EMULATOR% -core %CORE% -ratio %RATIO%</command>
<platform>snes</platform>
<theme>mmc</theme>
<emulators>
<emulator name="libretro">
<cores>
<core>snes9x_next</core>
<core>catsfc</core>
<core>snes9x</core>
<core>pocketsnes</core>
</cores>
</emulator>
</emulators>
</system>

Estou com problema em criar um game collection, eu faço toda a configuração do novo sistema no es_systems.
Aparece os jogos, menus e tema perfeitamente, porem os jogos nao entram, porem nos seus emuladores funcionam normalmente, alguém sabe como resolver isto, usei como base a linha do Snes.

<system>
<fullname>Mega Man - Collection</fullname>
<name>mmc</name>
<path>/recalbox/share/roms/mmc</path>
<extension>.smc .sfc .SMC .SFC .zip .ZIP .mgd .MGD</extension>
<command>python /usr/lib/python2.7/site-packages/configgen/emulatorlauncher.pyc %CONTROLLERSCONFIG% -system %SYSTEM% -rom %ROM% -emulator %EMULATOR% -core %CORE% -ratio %RATIO%</command>
<platform>snes</platform>
<theme>mmc</theme>
<emulators>
<emulator name="libretro">
<cores>
<core>snes9x_next</core>
<core>catsfc</core>
<core>snes9x</core>
<core>pocketsnes</core>
</cores>
</emulator>
</emulators>
</system>