Green/willow legs doesn't always indicate ameraucana. Case in point I have a young Buff orpington (hen)x Cream Legbar (sire) chick with the most willow /slate legs you could imagine. I bred her myself. I also have an ameraucana (hen) x CL chick with orange legs.
Cream Legbar Rooster over Buff...
They're beautiful birds, but I don't see any Ameraucanas :/
I agree that black and white one could very well be a cockerel.
Did you get them from an individual or a feed store?