I think that you are right that the one in the first picture on the left is a pullet and the other 2 with her are roosters. I don't see wattles on her which is a good way to tell. You can't really go by body shape at this age since Wyandotte chick's (should be) bodies are round in both sexes. Hard to tell for sure on the color of the rooster in the last picture but it sure looks dark blue to me. I see what looks like lacing and you would not see that on a black bird. Another picture of it in full sunlight from the side and a chest view might help

Hi Everyone,
I have a few chicks that I'm trying to sex, but I'm having a little trouble (in that I don't want to believe what I know is true). These chicks are all a cross between a Blue roo and BLRW hens.
I think I have two roos on the right and a hen on the left based on their combs, my confusion is just that they all seem identical so far in body shape and feathering that feels more pullet-ish. That's what's confusing me. Is there any chance they might all be hens? I can't remember how old they are at this point since we've had chicks coming out our ears.
Here's a shot of their backs.
And do you think this guy is black or just a very dark blue?
Thanks!