Are you loading each one manually or going through the ROMs and picking the cores it auto detects? Because I was manually loading each core instead of letting auto detect. Snes9x, Nestopia, FBA all loaded without a hitch, but as soon as I loaded a ROM on mGBA, the emulator crashed. I haven't tried loading a ROM and then picking a core, as that's what we're supposed to do know. What we can also try is the core that it crashes it, we can try to load that by itself (it's own app), to narrow down the issue.
Gonna do spam-testing, loading several ROMs in a row per core with the no. of cores I have, if that makes sense, a stress test if you will.
Like say with Snes9x, load five games in a row, then Genesis Plus, mGBA, etc.