Far Cry 6 has a tentative release date of 26 May 2021, according to the game's Xbox Store listing. Ubisoft is yet to announce its launch date officially after delaying it indefinitely. However, the Xbox Store is likely correct, as it accurately predicted many game launches earlier.
https://www.notebookcheck.net/Xbox-Store-listing-hints-that-Far-Cry-6-will-be-released-on-26-May-2021.505200.0.html