Yes, you need 2 female chickens to have sex so they can lay eggs. Everything about the chickens is wrong.
I don't know what realm Haldor got these eggs from but he should ask questions next time.
Would have rather had wild chickens in the game than rabbits, would like to tame all the things than just a couple of the things. Don't really like the concept of Haldor in general and having these things be gated behind other unlocks sucks.