Someone literally asked almost the exact same question like yesterday, there are two, Genesis Plus GX and PicoDrive (both are RetroArch cores but I believe they're made as standalone CIAs)what are your thoughts
is it a cia?
You could've also looked up the mentioned emulators to see for yourself if they were available as CIAs.(both are RetroArch cores but I believe they're made as standalone CIAs)