Aquaman 2 director James Wan discussed how the sequel relates to the DCU's always-changing status. Wan is best known for his work in horror films like the Saw and the Conjuring franchises and M3GAN. He started directing blockbuster action movies in 2015 with Furious 7.
Wan directed Aquaman in 2018, the highest-grossing DC movie of all time, with $1.14 Billion. Of course, with numbers like that, Warner Bros. had to make a sequel. However, the DCU has changed and evolved a lot since Aquaman. Warner Bros. and Discovery merged, and with it came several changes to their movies. For example, the Batgirl film was canceled after it already finished filming, Henry Cavill was brought back Superman and then let go again, Ben Affleck also left, and James Gunn was put in charge of the DCU. Finally, the long-awaited The Flash reset the DCEU.
In an interview with The Hollywood Reporter, Wan discussed making the Aquaman sequel. Wan was asked if he had to make any changes to Aquaman and the Lost Kingdom to fit with the DCU reset happens in The Flash. "I’ve had to make adjustments all along the way. The DCU has been through lots of different versions, and one of the things that was challenging about this film was keeping track of what’s going on," Wan said. "Fortunately, the Aquaman universe is pretty far removed from the rest of the world. We’re going to many different underwater kingdoms that are not necessarily related to what’s happening with the other movies and characters, so we’re stand-alone in that respect."
Wan makes an interesting statement by saying that Aquaman is a standalone film. The movie does not affect nor is it impacted by the other movies and characters in the DC universe. The underwater kingdoms in Aquaman are separated from what is happening in Metropolis or Gotham. However, Wan did mention that he had to make some changes to fit with what was going on in the DCU, saying, "So I can just tell my story on its own without being affected too much, but at the same time, I have to be mindful of what’s been happening."
Originally, Aquaman and the Lost Kingdom was supposed to be released before The Flash. This was before either of the films started shooting. The Aquaman sequel will now be released after The Flash, and there is no confirmation yet if the film will take place before or after The Flash resets the DCU. Aquaman and the Lost Kingdom likely takes place before The Flash reset everything, and fans might get a post-credit-scene of how Aquaman's world changes, similar to what the MCU did with movies that took place before the snap but came out after Avengers: Infinity War, like Ant-Man and the Wasp and Captain Marvel.
Source: The Hollywood Reporter