Hmmm, not purebred Cochins. They almost look like Cochin/Japanese crosses. Would buff crossed with black tailed buff give something that looks like that? It's definitely two single combed breeds that were crossed and one of them wouldn't have been feather legged since their leg feathers aren't as thick as you'd see on a Cochin. Another option that comes to mind is Dutch/Cochin cross, they look like they have a bit of a white ear and a very upright carriage with low wing carriage. Very cute birds though.