SGB features will not be judged as part of the competition since the judges do not all have the hardware to test. If you include them, they won’t disqualify your entry, but if your game relies on it your game may be excluded from being judged.
Thanks a lot for the clarification!
I think I'll go another route then, as being able to play the game I want to make would indeed require either an actual SGB+SNES or to use BSNES emulator (BGB does support most SGB features, but not all).
Thanks again for running this compo :)