This sounds like Kojima productions going second party or something similar to From Software doing Blodborne or the situation with Freedom Wars. Wich i'm super OK with it.
In the future Kojipro will be able to do games with other companies if they so desire, just like Insomniac.
Anyway this are great news all around, Kojima and co. are free to finally start developing wathever game they so desire.
It's likely KojiPro will be signing on for 3-4 games, just like the other second party studios.