Aside to the review: are you still collecting in the past year? I see the price of Action 52 (NES version) has more than doubled. I haven't bought a non-Switch game since August 2020.
So the Genesis version was actually made by a different developer, FarSight. Active developed the NES version internally with a pre-Atari crash dev cycle ("what's is a playtesting?"). The Genesis version appears to be a ground-up re-write rather than a port, hence the differences in some games. Interestingly, one of the people that worked on the Genesis version, Jay Obernolte, also worked on Color a Dinosaur. Can't make this stuff up.
So the Genesis version was actually made by a different developer, FarSight. Active developed the NES version internally with a pre-Atari crash dev cycle ("what's is a playtesting?"). The Genesis version appears to be a ground-up re-write rather than a port, hence the differences in some games. Interestingly, one of the people that worked on the Genesis version, Jay Obernolte, also worked on Color a Dinosaur. Can't make this stuff up.