What makes you think females are excluded ? Most females have hands, and hands are a pretty gender neutral part of the body, especially in emoji form.
Identified by what? Nail varnish?
Perhaps you could put a bow on the hand?
I hope you're joking :-))
It would be less arbitrary than the visual differences between the male, female, and gender neutral emoji which are pretty much differentiated by hair length.
I’d say there are more men with long hair than nail varnish.