It depends on what is "hiding" under the white. I have only dabbled in color genetics, but my understanding is that either you have a pure white, or just a dominate white. I'm sure i'm not using the proper terms here
Basically if you have a pure white, most of the chicks will be white, but if the white is just "covering" up other colors, you could end up with just about anything. If you got them from a hatchery, chances are it's a pure white. Bet on getting mostly white chicks, that's been my experience with crossing white hatchery birds.
I was disappointed too
With a white hen and a black roo, I had 75% white and 25% white with a couple black spots. I don't know what the next generation will do because they aren't laying quite yet.
Hopefully someone with more experience can tell you more.
Thanks, I haven't had standard cochens before. The buff roo is a MM free exotic. The blue roo came from a sale and is very full feathered and nicely colored. The white hen is from a sale too but she is not as full feathered as the blue. She was light grey as a chick and turned white. Guess there is only one way to find out what colors I'll get
Being light gray as a chick makes me think that there might be something hiding under there, maybe some blue. Usually white birds come from yellow chicks. Still, you won't know till you try. I hope you come out with some cool colors! I love cochins. I have some laying hens for eggs but my cochins are my favorite. They are the friendliest birds I've delat with. Good luck and have fun