The subject line speaks for itself. I'm posting this because at least two people (maybe more) saw that word and thought "horror movie" shudder shudder. Reskinning has nothing to do with horror stories and everything to do with using trademarked characters.
For example, I posted a series about "Owlman" - who isn't Batman. No, Owlman is just a billionaire who wears a costume and fights crime because criminals killed his parents when he was a child. He doesn't have a sidekick named Robin, but his young cousin helps him as the costumed hero Owlet. His enemies include Cat Lady, who isn't Cat Woman. No, she has cat based powers and lives in with her great aunt and her great aunt's hundred or so cats. And yes, there are spankings included in this series.
And so on. To be honest, Owlman is clearly based on Batman, but he doesn't touch on any trademarks.
I also wrote a series called "A Totally Original Superhero Story" where a young teenage boy (living in a group home) is given a magic power by a wizard. All he has to do is say a certain word and he becomes an adult in a superhero costume. He is given an instruction book to explain his powers, which he quickly loses. Yes, some might see this as Shazam! mixed with elements of "The Greatest American Hero", but it is reskinned enough that it doesn't impact trademarks. And yes, when the young hero makes mistakes one of the wizards shows up to spank bottom.
Another reskin is 50 Shades of Gray - which started life as Twilight Fan Fiction.
Another kind of reskin is any parody movie. For example, Star Wars became Space Balls.
Why do I worry about trademarks? To be honest, I don't, but the site does. It doesn't want to get a letter from a lawyer representing trademark owner. Which means I have to care, because any story I write that hits on trademarks won't be posted here. Yes, I have had a story rejected based using characters without reskinning them. | 
