I think the BR mix is a pullet. Cockerels have much lighter coloring and only the pullets have the dark wash down the front of the legs. And it's not sex linked because the mom was not the BR. To get a black sex link, you need a solid, non barred roo over a barred hen.
I'm not sure on the reddish one and the EE. It's a bit early to tell on them. Post pics when they get to be about 7 or 8 weeks. Usually by then you can get more definite answers.