Your goal is rather straightfoward to do. Just cross them and then raise the pullets each generation to maturity to see which ones are laying colored eggs and breed those with a purebred silkie and before long youll have silkie looking birds that lay colored eggs. If your goal is to have silkies with good or excellent type, that's another matter and will take a couple more generations.
This kind of cross or mixing isn't too rare. I see mixes with those breeds sold on here pretty often. I even have some colored egg laying silkies (and mixes)..
It does not matter which way the first cross goes, although generally an EE rooster has an easier time breeding the silkies than a silkie breeding an EE hen, especially if she is big and he has extra short legs of a good type silkie rooster.. They still can breed if really determined though... LOL
You cannot assume ANY rooster from the crosses or mixes having the colored egg gene even if his mother laid blue or green eggs. That is why you need to raise the pullets. A pullet that lays tan or brown eggs did not get the gene and so she will not produce any colored egg daughters- unless she is bred with a rooster who has it.
The first cross produces a normal looking chicken with a little leg feathering and a small crest.. do not expect a "silkie" in the first cross..
