the white patch I bet is what was making the pics look slightly bearded.
if the legs in fact are greenish in person, then you can pretty much certainly rule out Sumatra. Many people on here are like parrots, once one person says something they'll just repeat it, so you have to watch who you actually listen too some times haha.
Size wise on the chick, man there's no telling. That's hatchery stock for you.
I got in a bunch of old English game bantams several years back that I was gone use for color projects. None turned out anywhere close to the colors they were meant to be, and instead of tiny old English, they were 3 and 4 pound monsters.
That's just the nature of hatchery stock in general. They really don't adhere to any standard. Production is all they focus on.
It could be a runt, could be a bantam ee cross, could be this or that.
As it matures some you'll be able to tell more about it, and maybe narrow down exactly what all it has in it. She looks nice and healthy though, and from the thickness that those legs look to be, she may well grow into a big bird too once it's all over.
Keep us posted , I'd like to see her as she matures. and yes, there are solid black EE's too, thought they usually have a little color in the hackles on the males from various color genes in the mix, but hens seldom leak any color from the same matings.