Easter Egger ameracaunas come in a million colours and I have had 3 sex links and they looked different, two looking like this one. Sex links are mixed breeds made for laying and so they're colours are Not Pure, this is almost a poster bird to the ones we sell at the feedstore.
I don't think its a Dominique, it has a straight comb not a cushion comb. AndI don't think the other one is a Wyandotte either, wrong comb type as well and it should have more lacing by now.
I would say you have a buff orp, barred rock, and a black sex link.