My avian vet said there are intersex chickens who can show characteristics of both male and female. The vet said this in relation to my isa brown Whitetail who is uncharacteristically tall, lean and fierce — but she lays eggs. I also have a silver leghorn Lorraine who is in love with my black australorp Lillith. Lorraine lays eggs too —but she also has spurs, does the special dance for Lillith, side steps, hangs around the shed when Lillith is brooding/laying and is always very doting and patient towards the chicks.
I can’t really comment at all beyond what the vet said to me and my observations of my own flock but I do think chickens transcend the binary in all sorts of ways!