*Puts detective hat on*
Based on the job postings on Obsidian's website and LinkedIn its pretty clear that one of the three projects between Indiana and Maine is a AAA first-person single-player next-gen action RPG in Unreal Engine 4. The Combat System Designer job posting is particularly interesting because it begins with "Obsidian Entertainment is looking for a Combat Systems Designer with proven experience developing first-person melee combat gameplay to join our team of talented developers". Source:
https://www.obsidian.net/jobs/open-positions/design/1138-combat-designer. The emphasis on melee combat suggests that it might be a fantasy RPG, which makes sense since they already have a gun-focused RPG franchise going with The Outer Worlds. Rand al Thor, the Xbox YouTuber who had advance knowledge on Grounded, mentioned that in addition to Grounded Obsidian were working on a larger game which was "the one that Microsoft purchased the studio for". Source:
https://www.youtube.com/watch?v=lpFT1Fp7BrY&t=442s. I presume this is the same game, Chris Parker's long-rumored Skyrim-clone. But its worth noting that Playground Games are working on Fable 4, so it would be a bit weird if Microsoft had two Skyrim-clones releasing around the same time.
Two of the job postings mention multiplayer and Unreal Engine, but those might be for Grounded, so no reason for alarm just yet.
The other two projects appear to be either small-scale or cancelled projects.
Back in February Fergus said to Game Informer that "We have The Outer Worlds' team, which are the majority of our development. We saw the small group of people that are finishing up Pillars of Eternity and then we have two other teams that are starting things up." Source:
https://www.youtube.com/watch?v=3pjgB30XSzs&t=298. Those two teams were presumably Grounded and the big Microsoft game. But then what about the two other projects between Indiana and Maine? From LinkedIn we know that Matthew Perez started as game director on a project in January 2019, while Brandon Adler started as design director on an unnanounced title in October 2018 and was promoted to game director in July 2019. Josh Sawyer posted the picture of his new Project Missouri notebook on his twitter in July 2019 so Missouri appears to have been started around that time. Missouri is probably his rumored medieval autistic monk simulator. There was also rumors of a project being canned sometime in 2019. Then there's the comments made about both Chris Parker and Fergus wanting to be game directors now that Microsoft owns the studio, which puts the number of potential game directors at 5, not counting Tim, Leonard and Adam Brennecke (director of Grounded).
TLDR: I'm confused.