I May Need A Molly Expert

I have a goal of separating our 60 gallon tank so that one side is boys and one is girls. As some of you know last November my 5 year old insisted we replace her dead male molly with a very pregnant female. I said ok sure knowing full well we already had a tank full of males. Fast forward to today and we've had at least 5 sets of babies born in our tank over the last few months. Several to the original mommy molly and 1 set to an albino female we purchased later. Now I'm trying to figure out who is who as I separate the breeding age fish. I have a couple that I'm not 100% sure about. Anyone here know Molly's pretty well? If I post some pics of these few fish can you help me. Mostly my problem is when they are sitting still they let their back fish hang down like a female but when swimming they tuck it back.

 

Post pics .

 

If the analfin is a fan, its a female, the males' analfin looks like a sword.

 

As soon as I can get a good pic of the one in questions I will post it. At this point out of all the babies we have they all look like females and I only have like 5 males.

 

It can take months for males to show / completely develop and be noticeable .
All livebearers are born female .