Platy looks female... sometimes

I know how to tell the difference between a male and female platy. But this platy confuses me.
It swims around like its a male, but that anal fin sometimes moves and spreads open like a female.
It's hard to see, but there is a bit of a web between the body and the anal fin. The web isn't as pronounced as the females in the tank.
The fish itself is the largest of all my platies. Even bigger than the actual male I have in the tank.
The other males anal fin doesn't move.
So... Is this
Male or female? Or a gender confused platy?

I am unable to upload a video, so here's a YouTube link.

Looks like a male to me.

Definitly a dude

Thats a male