I'm pretty sure as long as one is female, and the other male they'll mate. That's how livebearers work in my understanding
It's pretty much color variations, just like in guppies the color doesn't matter, as long as there are males and females together. How long will it take could vary. If you see him chasing her then it shouldn't be too long. If you're going to separate them after just leave them together for an hour or two and then separate them. She should be pregnant after that, but there's no guarantee. Good luck!