Separating breeds is going to be tricky if you're using broody hens. Unless you have several hens that go broody dependably, trying to get the timing right is going to kill you.
So all your breeds run together, correct? And any given hen could be covered by any given roo at this time?
So, if you wanted to hatch say, BR chicks, you'd need to pull the BR hens away from the other roosters. You could have them with the BR roo or not at this point, doesn't matter. But, you need to wait a good 2 weeks for the other rooster's sperm to clear out of the hen's system. Then, you could put your BR roo in if you didn't already, and start collecting eggs to hatch.
The 2 week window you'll need to wait is what's going to make your timing such a challenge with a broody hen. If a hen goes broody, I don't think it would be healthy for her to try to keep her broody the 2 weeks clearing time, then 3 weeks for hatching eggs. I also think you'd have a high chance of the hen abandoning the nest before the eggs hatched. On the other hand, if you pull a breed for egg collection, then just hope for a bird to go broody, you're playing the odds a lot. The only breed you mentioned that goes broody at all reliably is the cochin.
It would be much easier if you had an incubator, for what you're wanting to do. Or just accept you'll have barnyard mix chicks.
