Yes, that may very well work.I guess I'm going to go against popular opinion. That Wyandotte brooded just as long as the other hen and if you are trying to maintain a level of broodiness in your coops or in your Wyandotte flock, I'd separate them with their respective chicks. I know space is at a premium, I think it is probably that way everywhere this time in the grow out season. If I break a broody early in her trance thats one thing, but once she hatches out chicks and proves to be a good mother to them, I'll let her keep them.
One concern is that the Wyandotte may be working towards killing the Rock's chicks. Survival of the fittest and all.
This happened to a person in California last month. Quite sad for them.
Another answer might be to put up a temporary wire fence between the two Mother Hens. That would not take up more space but would require one more place to provide food and water. I am getting swamped with this now. Thankfully my incubators are off now so hopefully I will be able to get the numbers down soon.