Molly behavior

I have noticed the female Mollies 'hovering' in place, vertically, as if to say "I'm ready to breed" to the males. Of course, I've seen the males doing something like this before too. Is this actually a signal to males in the tank to say they are prepared to breed? Or is it more like a resting position so they don't get tired out?

I recently had my Mollies in my 55 gallon with my Angelfish, but one female was pestering the Angels, and got some of the others in on the 'game' so I moved them to my 37 gallon Livebearer tank. After seeing posts about Mollies & Guppies cross breeding, I'm worried about this happening in my tank. I've actually had a male guppy chasing Platy & Molly males & females when I got him in the tank & thought he was either really confused, blind or extremely horny. After removing the Mollies, he started chasing female guppies, but I had to wonder about them cross breeding.

I've had brown Platy babies being produced from breeding my Mickey Mouse female with a Red platy male & wonder if it was a cross somehow...? Are there neutral Platy breeds out there that will produce whatever the males are? She was a female & was just sold to the local fish store in Lakewood. I also have a Hi-fin looking like a neutral/brown with a wagtail appearance. I believe she came from my blue Mickey Mouse Hi-fin female Platy & Red Wagtail Hi-fin male. She seems to be the only survivor so far, I haven't seen any others her size.

The Mollies I got were both Silver & Creamsicle Lyretail Mollies & I do believe the males of each color bred with both of the females of each color. The babies should look interesting....