In Avengers: Endgame, Captain America fought a younger version of himself. According to co-directors Joe and Anthony Russo, Thor almost had a similar throw-down in the film.
On the Happy Sad Confused podcast, the Russos confirmed they planned a fight sequence between Lebowski Thor and Buff Thor, which they discuss around 16:30 in the episode. "We did have that," they told the host. "There was a sequence where they finally confront one another in Asgard. I can’t remember exactly why we moved off of that. I think it got overly complicated and then we liked the Cap vs. Cap better."
Instead, they decided to go with a storyline involving Thor and his mother. "The storyline between Thor and his mother was so resonant. That was really more part of Thor’s journey and repair than confronting his former self," they explained.
Directed by Joe and Anthony Russo, Avengers: Endgame stars Robert Downey Jr. as Iron Man, Chris Evans as Captain America, Mark Ruffalo as Bruce Banner, Chris Hemsworth as Thor, Scarlett Johansson as Black Widow, Jeremy Renner as Hawkeye, Brie Larson as Captain Marvel, Paul Rudd as Ant-Man, Don Cheadle as War Machine, Karen Gillan as Nebula, Danai Gurira as Okoye and Bradley Cooper as Rocket, with Gwyneth Paltrow Pepper Potts, Jon Favreau as Happy Hogan, Benedict Wong as Wong, Tessa Thompson as Valkyrie and Josh Brolin as Thanos. The film is now in theaters worldwide.