Replying to "Do you think DLSS in metaphor is possible?"
Short answer: Maybe but it would be considerably more work than for Persona 5
Longer answer: I think the only reason we have motion vectors in Persona 5 is for the motion blur during those 3 seconds in title sequence where Joker is swinging through the buildings and it was more work to have multiple permutations for materials so they just are generated for the entirety of the game. In metaphor they removed that, but not entirely Vertex shaders the previous transformation matrix and output the previous NDC coordinates it's just that motion isn't written to a render target. And then there's the bigger problem that in Persona 5 skeletal meshes also receive the skinned vertex positions from the previous frame, which in metaphos is missing entirely. So the 2 most difficult things I think would be required are
1. Skinning is done in a compute shade so the transformed vertices need to be cached for the next frame, and then need to be matched to draw calls in the current frame
2. Update all material pixel shaders to also output motion vectors to separate render target