Arkane Studios is a pretty big developer. To the point that, at the moment, the team that is developing Deathloop for PS5 has nothing to do with other teams that are working on other major projects for the studio.
One of them is a new game being developed by Harvey Smith (one of the founders of Arkane), which has the same team that was commissioned in his day of Dishonored, or the last Prey. And it turns out that project is why Smith is not currently involved in Deathloop.
The information comes from a complete interview that our Vandal colleagues recently conducted with the creative. In this, Smith confirms the information discussed in the previous paragraphs, but has not revealed more details about the nature of that project.
And although we might think that it could be a sequel to one of those two aforementioned sagas, some leaks from the past point rather to a possible new IP. Without going any further, a relatively recent job offer mentioned that the team was developing a new game of “immersive simulator”. Although you also have to remember that Arkane is working on more than one secret project right now, so it might not be the same.
What is very likely is that it is a project very focused on the acquisition of ZeniMax Media by Microsoft (which, obviously, includes Bethesda and Arkane Studios).
However, it is not clear at this point how Microsoft will handle the releases of those games. They could be totally exclusive to Xbox on consoles, but there is also the possibility that they are a “best on Xbox” or a “first on Xbox”, as they themselves pointed out a few months ago. At the moment, there is nothing clear or “official” about it.