We've received word from Rising Star Games co-founder Brjánn Sigurgeirsson about the possibility of Deadly Premonition 2 on PS4. He says the game is a "Switch exclusive at launch" and that the publisher is "not discussing other platforms at this stage."
Given this bit of information and the game not being published by Nintendo, it seems very likely to be a timed exclusive and will at the very least see a PC release.