The game STALKER 2: Heart of Chernobyl by the Ukrainian studio GSC Game World, as it turned out, is being created on the newest Unreal Engine 5. The company itself announced this on its Twitter page.
GSCs were previously known to use the Unreal Engine, but no version information was available. Probably, initially, the studio could not divulge details. Now it turns out that STALKER 2 will be one of the first games on the new engine and, possibly, the first single-player game.
At the moment, there is officially only information about the transfer of Fortnite to UE5, and this may happen as early as September. STALKER 2, in turn, will be released on April 28, 2022. Yes, there is still time for the release of some other game, but you need to understand that such a game should have been in development for a long time.