Yes that part I understood. It's hard to find pea comb true blue layers around here (ameraucana, etc) so I was wondering about egg color alone but the sheer insane amount of time and birds it would take to test breed to find the O/O is staggaring and I've quickly come to realize finding ameraucanas would be easier.
If you are located in the USA you can order a few Easter Eggers pullets. they get their Pea Comb and Oocyan mutation from the same chilean stock and many of them look just like Ameraucanas just keep in mind that a few will lay pink colored eggs even if they have a Pea comb due to allelic crossover. keep the ones laying blue eggs and have pea comb. you then cross them with your best rooster(a son of your best hens that lay chocolate colored eggs) The best F1 hens(with pea comb) are bred back to the same rooster.