I want to believe that it's fake, because everything in the list except Ninja Gaiden (which already was leaked) didn't make much hype for me. With DOA state I prefer to believe Hayashi more about his promises for sequel.
The situation is really interesting. Part of TN definitely worked on DOA7 before early 2021. Project was cancelled.Then after Shimbori left, Hayashi hinted on DOA and NG sequels, and there's high possibility that NG sequel already in works, so small chance for DOA exists. They have at least some basis for it, not from scratch
Team Ninja new projects in development (leak by programmer working in Koei Tecmo), no DOA7 through:
1. Sangokushi Action
2. Nioh 3
3. Ninja Gaiden
4. Ronin (original title, release in the end of 2023, platform s: PS 4/5, Xbox series, Steam, they plan to sell 5 millions copies of this game)
About Dead or Alive: small team worked on DOA6 support and early DOA7 development. After Shimboris departure this was cancelled.