Still, with other heroes from elsewhere in the DC multiverse expected to show up alongside these Batmen, it’s looking like The Flash will be quite the cinematic event. Furthermore, this may not be Michael Keaton’s swan song as Batman, as it was reported that he could end up serving in a “mentor capacity” in other projects, such as Batgirl. However, that tidbit of news came out before Ben Affleck’s Batman return was announced, so if plans are made to feature more of Batfleck in the DCEU, it’s unclear if that will interfere with what was being hashed out for Keaton.
Article source: https://www.cinemablend.com/news/2555064/yes-dc-is-already-selling-merchandise-with-michael-keatons-batman-because-why-not