The real studio Sony needs to buy is both affordable and would make for amazing games. Would be great for the industry.
The answer to that is:
Level-5
Combined with Asobi, they would be the Studio Ghibli of video games.
I'd love to see them do a 3D reboot of Alundra with shades of Dark Cloud, Rogue Galaxy, and Breath of the Wild.
Level-5 wouldn't cost nearly as much as say FromSoftware or CDPR, but would give Asobi and Sony an answer to Zelda but a little bit more dark and mature, while maintaining a specific type of style.