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The One, a 2001 Jet Li martial arts/sci fi film about a multiverse-traveling law enforcer who must hunt down alternate versions of himself, sounds like a close fit. DISCLAIMER: I never actually saw it, I am familiar with the basic storyline though.
It wouldn't be The One.
Yeah, that's not it, there was definitely a forum, and the life/wife stealing was a big part of the plot.
Writer, or something. And... a button? 🖲️
That sounds like the end part of a book I read, but I don't know if it has been made into a movie. The original German title is a language mix: "Dark matter - Der Zeitenläufer". The protagonist escapes from some high-tech organisation by using a device that lets him go through alternate universes, and when he arrives in his original world he finds out that many duplicates of him from other universes have arrived there, too
Edit: the forum & wife - he receives an invitation to an online forum that is used by all the other "hims", and they discuss more or less violent ways to decide who will present himself as the original her to the hero's wife
Edited by Bernd Sanity is for the weak
Definitely sounds like the book "Dark Matter" by Blake Crouch — has all the elements mentioned.
I actually have no idea of the genre as I am pretty sure it was described to me a while ago (that or my brain made it up). Anyhow, there is a guy with a wife and children who finds that alternate reality versions of himself keep coming by to try and steal his life. After fending them of for a while, he joins a forum of himselves and realizes that he is not the original him in that universe. IN the end, the selves ask his wife to choose, and I think she chooses him, since she knows him best, but many of them don't give up and there is a chase and it gets hazy after that but I think they either all jump to another dimension or kill off the others.