During a conversation at Justice Con 2021, Snyder said Wayne T. Carr filmed a scene in his driveway as the iconic superhero.

“He’s an amazing actor, an amazingly kind gentleman,” Snyder told the Nerd Queens and Wonder Meg during the Saturday evening panel.

“I said, ‘Look, there’s a chance that this doesn’t make it in the movie,” Snyder added, saying, “I’m not 100% sure he thought it was real, legit.”

After about three years of fan rallying, HBO Max released the “Snyder cut” of 2017’s “Justice League” on its streaming service on March 18. Though the film restores a few diverse roles, including a trimmed-down Cyborg and Martian Manhunter, Snyder had planned on introducing a new Green Lantern.
Warner Bros. wouldn’t allow it.

“We did have a Green Lantern scene in the movie that the studio asked me to take out that I did also shoot here in the driveway with an amazing actor who was going to play John Stewart,” Snyder told Sean O’Connell, Jake Hamilton, and Kevin McCarthy of the ReelBlend podcast.

“Then the studio, when they saw the movie, and they saw that I had done every single thing that they had asked me not to do, we had come to a bit of a loggerhead,” Snyder added.

At Justice Con 2021, Snyder said he met Carr through Ray Fisher, who plays Cyborg in the “Snyder cut.”
“Ray [Fisher] introduced me to him. He said you should check this guy out. He’s awesome,” Snyder said.

The director then looked at some of Carr’s clips before calling him up on the phone a few times to talk about what the role might entail.
Carr’s Green Lantern would have appeared at the very end of “Zack Snyder’s Justice League,” meeting Bruce Wayne in place of Martian Manhunter.

“We had made him a CG suit and because it was COVID and we couldn’t really do a real suit,” Snyder said when asked whether or not a suit was made for Carr. “The mandate was to make it look as physical as possible.”
The Green Lantern scene was supposed to play at the very end of the film. He was supposed to be one of two Green Lantern characters who Bruce Wayne interacted with, not the Martian Manhunter. (Snyder said at Justice Con the other Lantern would have been Kilowog.)
When the studio asked Snyder to remove Green Lantern, part of Snyder’s compromise was to add more of Martian Manhunter into the movie. He also got the Batman versus Joker scene.
Both the extra Martian Manhunter and Joker scenes were filmed in Snyder’s driveway and backyard, respectively.

Courtesy of Yahoo