I would guess they will be black with some lacing on their necks. I have one all black, one with white markings on he face, and the rest have brown lacing or stripes on their necks and heads. All mine are pullets.
The cockerels I had were much more colorful and had a lot of coloring around...
Great thread! I have a Cream legbar x Ameraucan rooster that I'll be crossing with my Marans hens in the spring. I also have an F2 OE and one EE that I'll be breeding him with as well. Unfortunately it will be a whole year from now before I find out what color of eggs the offspring will lay.