The Batman Part II will not be part of James Gunn's DCU, which brings both benefits and drawbacks. Gunn and Peter Safran came aboard as heads of the newly formed DC Studios in late 2022, formulating a plan for a new DC Universe that will encompass movies, television, and gaming. Gunn and Safran's plans naturally include the Dark Knight, who will appear in The Brave and the Bold, but this also made addressing the future of Matt Reeves's The Batman franchise necessary.
https://screenrant.com/batman-2-no-dc-universe-connection-effect/