Hi.
Hen chicks, mainly show the long, short, long, short fan like wing feathers, in a full wing. Try YouTube.
Hens present as they grow with rounder feather on the neck, back and wings, their legs ar thinner than male ones, and I find hens seem to have a slight ridge of feather near the start of the Airplane 747 style upright tail (!)
And many chicks even after a week or so, females grow wing and tail feathers more quickly than males.
Males, are born with massssive feet (!)
Have wing feathers that are long, long, long, and taper off to shorter ones mid wing onwards. Some breeds are feathered on the legs on the males (depends on the breed criteria.)
Roosters to be are more bolshy, in seeking feed, play, and chest bumping.
Black Copper Marans males have firey copper feather sprouting from their chick teen neck feathers !
I have sexed the gender better by looking at wing feathers, feet size, tail shape, and character way before the comb or wattles show !
One of my Cuckoo Maran's Hen has massive wattles, to that of her sisters. She is my best egg breeder, and doesn't crow ! However, she likes to think she rules the roost.
Hope this helps.
If you want your own fertile eggs, a second Rooster is useful. Boys brought up together, if of nice character, can live by themselves, together. And be introduced for family matters, as needed !
If showing fighty tendencies, sell as a rare breed Mr & Mrs to others chicken fanciers.
( Pssst, or, he can go on to an Alps holiday one way to the freezer !)
Have several girls n guys chick wise following above. Don't know or want to vent sex... Way to scary to learn