They will still be Easter Eggers, if you put the rooster you have over the pure bred Ameraucana, the chicks will be Easter Eggers.
Maybe you will hit the jackpot and hatch two female and one male from each color. Then you could set up two breeding pens, one for the Blue/Black/Splash and one for the Wheaten.
If you can tell the eggs apart, between your easter egger girls and the Ameraucana girls, then you can put the Easter Eggers with which ever Ameraucana group you want. People do like Easter Eggers, they are fun since the colors vary so much, and some easter egger lay better than Ameraucanas.
If you can't tell the eggs apart between the Easter Egger girls and the Ameraucana girls, you are then stuck with three separate breeding pens.
Or, you can toss all of them into one single pen, all chicks will be Easter Eggers, but you will hopefully get good blue egg layers, and many people would be happy with that.
Remember, that if you put the Blue/Black/Splash Ameraucana WITH the Wheaten Ameraucana, the chicks will be Easter Eggers, not Ameraucana, since they will no longer conform to any Ameraucana color.