They look like Rhode Island Red, Speckled Sussex crosses, but what is throwing me off is the yellow legs. All of my RIR - SS crosses have white/pinkish legs and I think those are dominant over yellow. I'm not good enough with genetics to know if yours could have yellow legs and still be that cross. (The rooster in my profile pic is RIR - SS.)
To me the upright stances, especially the one on the left, indicates some kind of game breed was involved in the cross. They're definitely mixes. Nothing wrong with that. They're beautiful.