Set photos from The Flash will reboot the DCEU to have Keaton's Batman take the place of Ben Affleck as the universe's main version of the Dark Knight. The changed timeline seems to be responsible for Batgirl teasing Robin's role in his past and setting up Nightwing's possible future.
If Robin is in Batgirl and connected to Michael Keaton's Batman, it will presumably be Dick Grayson as the boy wonder. However, Batman's role in Batgirl raises an intriguing possibility about his possible Robin. Keaton's Bruce Wayne is not expected to still be an active hero who has a sidekick like Robin, as his DCEU role has been compared to Nick Fury's in the Marvel Cinematic Universe. That could mean the Batgirl art featuring Robin depicts a time in the Dark Knight's past when he and Robin were much younger. If that is the case, then Dick Grayson would be much older by the time Batgirl happens and likely isn't the superhero known as Robin anymore.
Dick Grayson being Batgirl's Robin can be where the DCEU formally introduces its version of Nightwing. This can happen with or without a physical appearance by him, which could be dependent on if Warner Bros. casts an actor in the role in time. If they don't, Batgirl could use the art of Keaton's Batman and Robin to incite a conversation about Bruce's previous proteges before working with Barbara Gordon (Leslie Grace). Dick doesn't need to appear in that case, as Batman can simply explain what happened with his original Robin. Otherwise, the former sidekick could appear as an older and experienced hero who hasn't been at Batman's side in years as he's been fighting crime in Blüdhaven as Nightwing. In doing so, Batgirl's Dick Grayson can revive WB and DC's plans for a Nightwing solo movie.
Plans for a DCEU Nightwing movie started to form in 2017 when The Lego Batman Movie director Chris McKay was hired to helm Dick Grayson's solo film. He worked on the movie for a few years, developing a script that explored aspects of Dick's origin, tackled his complicated relationship with father figure Batman, and focused on a revenge story. Details like the movie's villain or release date were never revealed before McKay shifted his focus to other projects as the DCEU took a new direction. This led many to believe Nightwing was essentially canceled, as McKay moved on to making The Tomorrow War and then chose Renfield as his next project.
Now that Batgirl's Robin tease indicates Dick Grayson has some type of role in the movie, it is possible the DCEU Nightwing movie is being revived by WB and DC. There might not have been much movement on the project in recent years, but the interest from the studios in Nightwing as a character is known, as is the desire to have multiple Batman-related franchises. Including a Dick Grayson tease in Batgirl is too significant to not be an indication of the studio's future plans. An official decision on Nightwing could wait until after Batgirl is released and the studios see how audiences respond, but it certainly seems like Dick Grayson's DCEU debut is trending in the right direction.
