Status: Unannounced, but strongly rumoured
We know that Warner Bros resurrected Avalanche Software to create a AAA title for consoles, and we also know that at one point it was working on some kind of Harry Potter-themed role-playing game. Prototype footage of the title, showcasing a character creator among other things, leaked online a while back – and the studio has continued to aggressively hire ever since. Given development schedules, it’s likely that this will be at least cross-gen – assuming it is still in production, after all.
Status: Unannounced, but an educated guess
Developer Guerrilla Games is hard at work on something, and you don't have to be a genius to assume that the project in question is a sequel to Horizon: Zero Dawn. The new IP was a smash hit on PS4, and the studio's reputation for pushing hardware limits makes the hypothetical Horizon: Zero Dawn 2 a strong candidate to show off the upgraded power of the PS5. Whether it'll be a next-gen launch title is up for debate, but we wouldn't be at all surprised.
Status: Dated for PS4, but given release window, an additional PS5 release seems likely
Just like Death Stranding and Ghost of Tsushima, it's not hard to envision The Last of Us: Part II as a cross-gen title. Another PS4 game that's settled with a long development cycle and a 2020 release date, developer Naughty Dog's pedigree is abundantly clear, and Sony will want to ensure that this sequel gets as much attention as possible.
Status: Announced, but due out in 2021, when PS5 will likely be available
A narrative-driven action adventure game from Daedalic Entertainment, The Lord of the Rings: Gollum will launch on “all relevant platforms” in 2021. Considering that the PS5 is rumoured to release in 2020, this means that we’ll almost certainly see it on Sony’s next-gen system. This wouldn’t rule out a PS4 release either, but it’ll likely be cross-gen if that’s the case.
Status: Unannounced, but seemingly inevitable given the success of Marvel's Spider-Man on PS4
Another seemingly inevitable sequel, Marvel's Spider-Man 2, or whatever it happens to be called, would almost certainly be a PS5 title. The seriously impressive success of Marvel's Spider-Man on PS4 will have already been enough to greenlight this hypothetical project, and as long as it's something that Sony and Marvel want (why wouldn't they?) then it's going to happen.