Apparently, this partnership is only coming to fruition due to the persistence of Yoko Taro, who approached Saito about working together on a project in 2019 and persisted with an hour-long pitch to convince him. Saito was initially completely against the game, but relented in the end.
Saito stated that he would take it back now if he could, according to SiliconEra— let's just hope he's joking though, right?
The duo revealed they are also working on a title that both are more enthusiastic about, and they plan to release it before the game that Saito is less-than-enthused-about.
With how vague this talk show reveal was, it's probably a sign we won't hear anything concrete on either of these games until the spring.