If neither of them passed they wouldn't be side eyed, and a cis woman/gnc cis man or the other way around would also be side eyed.

It's still m/f, public people's response doesn't matter because people will side eye you for wearing a fluffy pink ball on your hat if you're masc passing, and also I hope you're not cis because if you are, you trying to use trans people as an excuse to insert m/f into a kink meme that's explicitly for non-m/f couples is low.