Jason Inman of DC All Access took part in a YouTube video answering a fan's question whether or not Green Lantern will be in the Justice League movie. While what they discussed regarding Green Lantern first appearing in the DCEU is pure speculation, Inman did whisper to the camera, "It's going to be Hal Jordan."
In the comics, Hal Jordan is a founding member of the Justice League.
Inman also goes on to state he thinks Kyle Rayner will be in the Green Lantern Corps movie.
"I do think we'll see Kyle Rayner in the Green Lantern Corps movie," Inman said. "I don't think he wil be a main character, but.. I think they are going to name-check him. I'm pretty certain.. I have a feeling they will name-check all the Earth Lanterns in the Green Lantern Corps movie."
Regarding Green Lantern in the Justice League movie, Inman stated he thinks either Green Lantern or the Green Lantern Corps will get mentioned. Inman did note, "I don't know what it will be," and went on to say it could be something like a Green Lantern Ring featured in a scene with Steppenwolf.
Inman further speculates that something will happen causing the Green Lantern Corps to return to Earth in Justice League, with the Green Lantern Corps featured in Justice League 2 and setting up the DCEU following that. Inman says he thinks Hal Jordan and John Stewart haven't returned to Earth in a long time.
It's currently thought Zack Snyder may be holding off on using Green Lantern in Justice League because of the failed 2011 Ryan Reynolds movie. However, A couple of Comic-Con's ago did see Green Lantern Corps movie concept art released, so Green Lantern in Justice League is a definite possibility. The Green Lantern Corps movie is said to be coming out in 2020.
Watch the video for more talk of Green Lantern in Justice League and the DCEU:
"Justice League" has a November 17, 2017 release directed by Zack Snyder starring Ben Affleck as Batman, Henry Cavill as Superman, Gal Gadot as Wonder Woman, Jason Momoa as Aquaman, Ezra Miller as The Flash, Ray Fisher as Cyborg, J.K. Simmons as Commissioner Gordon and Willem Dafoe as an Atlantean.