Blue Andalusian or Blue Orpington...or other?
Oops...need photo :D
Well I can tell you that Blue Andalusian should have grey legs, or legs with some grey wash as a chick.
A Orpington will have white/pink legs...although I've noted the blue variety does get some grey in the legs as well
It may be hard to distinguish the chicks early but will be very easy to tell as they grow adult feathers and bodies.
Keep working on a photo upload as that would really help us.