I think its female, if it's about to lay, bright red comb and wattles are typical. She's 18 wks, so just about to lay. Don't see any male feathering, which would have showed up by now usually.
Mixed breed for sure. Now, does she lay colored eggs or brown? Can't tell from looking at her. If she lays blue, green, or olive, she is a non-standard EE (if you define EE as a mixed breed that lays colored eggs). If she lays tan or brown, she's a brown egg laying mixed breed chicken. Her parents may very well have been EEs, but if she lays brown, then she missed the blue egg gene.