I have had several chicks to feather out like that. Gender, have no idea, but the ones that feather out that way usually end up being pullets; colored like brown leghorns. There are several that end up those colors, partridge-colored. My guess partridge pullet of some type, probably plymouth rocks with the yellow legs. Some of the Dark Cornish's look like that as they grow too though, or even the Wellies. Good luck, they are cute. HenZ