(https://nintendoeverything.com/wp-content/uploads/Batman-Arkham-Collection.jpg)
So it seems French distributor WTT may have let the cat out of the bag early. WTT posted a listing on their website (since removed) for a "Batman Arkham Collection" for Nintendo Switch, with a tentative release date of August 31, 2022. Such a collection could include any combination of Batman: Arkham Asylum, Batman: Arkham City, Batman: Arkham Origins, and Batman: Arkham Knight. Arkham City and Arkham Origins were the only ones to release for a Nintendo console in the past, having been available on the Wii U.
https://www.wtt.biz/batman-arkham-collection-switch-c2x37076235