Edit: it posted by mistake when I was halfway through. I've got it fixed now.
I am assuming that each breed is supposed to be a purebred. If the labels are actually the mother's breeds, with a single rooster siring them all, that would make a big chance in the situation.
Going through all the breeds one by one, we can rule most of them out:
The chick is not a Barred Rock (wrong color, and Rocks do not have feathered feet.)
The chick is not a black Australorp (color looks wrong, and Australorps do not have feathered feet.
2-Lavender/Black split to Lavender Orpingtons
You ruled this out, because both of them hatched and you identified those two chicks.
You ruled this out, because none of them hatched.
The chick is not a Rhode Island Red (wrong color, and Rhode Island Reds do not have feathered feet)
I am ruling this one out, because the chick color is badly wrong for a Salmon Faverolles (although they do have feathered feet.)
The chick is not a Welsummer (wrong color, and Welsummers do not have feathered feet.)
Maybe?? The color looks wrong to me, but not too badly wrong, and Marans can have feathered feet.
I agree with you that this one seems most likely.
Can you get a picture of the head with comb? That might help a bit (Easter Eggers can have any kind of comb, but Marans would only have a single comb. So if the comb is not single, that rules out the Marans, leaving Easter Egger as the only possible option.)