Most if not all of these Taiwanese pirate Mega Drive cartridges have custom mapper hardware that needs to be emulated for the game/collection to work properly. I can't find any public documentation on these aside from this page (and the linked references), which has useful information but is not complete:
https://segaretro.org/Mega_Drive_Unlicensed_Game_Emulation_Notes
For some of them it's as simple as copy protection that expects specific memory addresses to return specific values on reads (probably a checksum), but some of them seem to have more complicated ROM banking hardware.
Most if not all of these Taiwanese pirate Mega Drive cartridges have custom mapper hardware that needs to be emulated for the game/collection to work properly. I can't find any public documentation on these aside from this page (and the linked references), which has useful information but is not complete: https://segaretro.org/Mega_Drive_Unlicensed_Game_Emulation_Notes
For some of them it's as simple as copy protection that expects specific memory addresses to return specific values on reads (probably a checksum), but some of them seem to have more complicated ROM banking hardware.