With the Easter Eggers that I have bought, some lay green and some lay blue eggs. It depends on the hen and roo in terms of what the offspring will lay. So the color she hatches out of might not be the color she lays (olive eggers come out of hens that lay blue/green eggs mated with a roo that lays brown eggs for example sometimes).
So if you don't have room to just buy a bunch of EEs to see what you get, and you definitely want a blue layer, then you might need to go to a breeder or buy a hen already laying.
EE's are basically non-standard and mixed bred ameraucana type chickens. Many of them lay a blue-based egg with varying amount of brown pigment on top of the basic blue eggshell, leading to green and olive coloration. Some lay a "pink" egg, which is basically a brown egg.
There are only 2 colors of eggshells, white and blue. Brown eggs are white shells with brown pigment layed over the outside. Green eggs are blue shells with some brown layed over the top. So a purebred araucana or ameraucana would be less likely to have any brown pigment genes, and more likely to lay a bluer egg. Mixed bred or EE hens would be less likely to have pure blue egg genetics.
Thanks for letting me know about the way the shell is colored. I didn't realize that. I noticed today my pullet Smokeys egg was more blue then her first green eggs. They went from olive color to lighter green and today it was practically blue. Interesting.
As chickens lay they have less and less pigment to apply, so brown eggs get lighter the longer the hen lays. Your hen probably has less pigment to add to the outside of the shell, leaving them bluer in color.
I just read someone on another board saying this is a myth and that there is only white eggs, but I've read studies that the blue is in the shell and that brown is added at a different stage. Do you have any good links to support this?