Good luck, but it's not like the female wears lipstick.
Perhaps if there were a similar appearance-based seed sexing technique for other seeds, (flowers, veggies, fruits...) I'd think it's possible for cannabis too. But from what I've read and seen, I'm sorry, but I feel you are barking up the wrong tree.

Google something like "determine seed sex by appearance". See if it's possible with ANY plants seeds, and go from there. :thumbsup: