I'm sure not a genetics expert, but I think pea combs are mostly dominant and he looks to have a pea comb that is already showing 3 bumpy ridges as cockerels get. Very young pullets have a single narrow ridge down the center (and most cockerels start that way too). The gene for blue shells is very close to the pea comb gene on the chromosome, so those traits usually get passed on together (not 100%), so he should be carrying at least one gene for blue shells.
Leg color, I'm not sure on. My feed store EEs usually start out with light colored legs that darken with age, but your chick looks to have white skin, which is confusing. Is it half Leghorn? Leghorns have yellow skin, so not sure where white wold come from.
I would love it if you could update as he grows. I want to see if he is actually male and how he turns out.