Initially, Physint was created with PlayStation's support as a next-gen project, and after Sony's refusal, Kojima Productions received support from Xbox, which became the game's publisher. This raised questions about its appearance on PlayStation consoles.
In an interview with IGN, Kojima was asked about a PS6 version. The creator of Metal Gear Solid neither confirmed nor denied it:
I don't know the answer to that question – you should ask Xbox. However, I'm not sure. In previous statements, Xbox has taken the approach that it wants to reach as many players as possible, regardless of platform. I think everything will be announced later. For now, I'm not sure and can't say anything.
Physint is in the early stages of development and its release is not expected anytime soon. The main point at the moment: the PS6 version is neither confirmed nor canceled, and Xbox will make the final decision on platforms.