I have try your reicast bin.
Do you think it's possible to change default bios directory to the bios general directory instead of /storage/.local/share/reicast/data/ (i did not found if there is a possibility to change it in emu.cfg) ?
So I put dc bios in /storage/.local/share/reicast/data/
I add this entry in es_systems.cfg :
I also add (try to) my xbox360 controller mapping :
evdev_mapping_1 = <path to mapping file>.cfg
but it seems to be rewritten at each start of the emulator so I do a chattr +i on emu.cfg so controller OK.
Marvel vs capcom 2 start but is not playable the sound is crackling and fps is low (to compare reicast in retropie allow to play mvc2 just some 2D glitch to note).
I'll check If there are specifics parameters used in the retropie reicast config as I haven't change anything in this run.