From a legal standpoint, there is absolutely zero percent likelihood any corporate lawyer at Disney would even allow a hint of using other properties before a $71.3 billion deal is finalized. Marvel Studios will already have a plan on what happens with the former Avengers Tower, and it is absolutely not Baxter. Maybe Feige has possibilities open in his head in the future, but none of it can be written down, spoken about, or even suggested at. There is just way too much on the line way beyond his or even the entirety of Marvel Studio's pay grade.

And from Occam's Razor's perspective, it probably is Oscorp. I'll honestly be surprised if we don't see Norman/Harry in the 3rd film (and I would actually bet to see a teaser in Far From Home). The "Moving Day" plotline was a big part of Homecoming and the renovations were featured in the trailer, and it would make way more sense to introduce Oscorp first instead of Baxter in the Spider-Man solo films.