I don't think it's a Speckled Sussex, my speckled Sussex had different colored legs and by the time they got to the stage this picture shows you could noticeably see where the light colored speckles were going to be.
No feathers on the legs, Don't think it's a brahma. Could be an Easter Egger, the legs look like they have a greenish cast. Some of my Easter eggers looked very similar to this. It also looks like the comb is barely visible so could be a pea comb.