I heard there are Game Gear to Master System conversions being

Do you want to make a repro, or just to play on an emulator? Most SMS emulators also emulate GG.

I think since it's being converted to master system the extension should be changed to .sms.

Although it doesn't really matter, the emulator will read the rom's header to determine which system to emulate instead of the extension.

>>3619524
>>3619518
Play em through an everdrive.

>>3619534
I've played a few of them on a GG everdrive with the .sms extension.

The extension is only to help sort files. You could rename it to game.jpeg and it would run the same.

gamegear displays more colors and runs at a different resolution, all hacks are more than simply changing the extension. do your own research fucknuts.