There has been much discussion and speculation over whether certain DC movies like The Batman take place in the main DC Extended Universe or alternate ones. Luckily, DC film boss Walter Hamada provided a little more clarity on the subject at DC FanDome.
During DC FanDome's "Multiverse 101" panel Hamada made it a point to mention that the Wonder Woman, Aquaman, The Flash, and the other Justice League characters to appear in the DCEU thus far exist in the same universe, while the version of Batman in The Batman exists on a separate Earth in a different universe, saying that "there's one Earth of this beginning Justice League and there's another Earth where there's this growing Year Two Batman," and that "Joker is not on [Justice League's or The Batman's] Earths."
Hamada also made sure to note that the company is currently focused telling strong individual stories rather than working to build an Elseworlds universe, but is willing to make more movies set outside of the main universe if filmmakers deliver pitches that are strong enough. However, he noted that Superman: Red Son, a movie some fans speculated was in the works, is not currently on the production docket.
WHAT THIS MEANS
While we know The Flash (which is set in the main DCEU timeline) will put the spotlight on the concept of the multiverse, Hamada's statement implies it will be used more as a fun facet to connect different DC projects when the company wants to rather than a major part of a lot of the shows and movies going forward. The company's willingness to branch out and not force themselves to set every project in the same time could very well prove to be one of the brand's strongest assets, as it allows filmmakers to take the characters and worlds of the DC universe in virtually any direction and put out a variety of different stories.