The developer of Psychonauts 2 confirmed the delay in addressing the E3 2019 announcement that it has been acquired by Microsoft:
As you just saw, E3 kicked off with us sneaking into the Microsoft press briefing to adorn Phil Spencer in a Psychonauts shirt. We then snuck past Keanu to announce that we would be joining Xbox Game Studios, and that Psychonauts 2 would be published by Microsoft (instead of Starbreeze) as a first-party title. Now, before anyone panics! We have confirmed that we will be able to honor Psychonauts 2 for every platform that we have already promised here, and that includes bringing the game to PlayStation 4!
There really shouldn’t be too many other noticeable changes for you at all, at least not for a while…with one notable exception: We’re now targeting next year for release. We know it’s always disappointing when you have to wait a bit longer, but we also know that you are an amazing, supportive bunch, who—just like us—want the game to be as good as possible. So we’re hopeful you’ll understand!
Psychonauts 2 will now be released for PS4, Xbox One, and PC sometime in 2020.