While the PC version of Nier Replicant may not be as disappointing as Nier Automata's port, it still has some problems. As Julie Muncy said in her review, "The technical aspects are much improved over the original, which struggled to maintain 30 fps, but they're not quite up to contemporary standards." She experienced technical problems including "serious frame drops when I accidentally unplugged my controller, or a persistent issue where my mouse point kept reappearing on my screen during cutscenes, which was not great for the game's sense of gravitas."
Additionally, players with monitors that have refresh rates over 60hz are finding certain animations are tied to framerate, and when they exceed 60 fps the protagonist zips around so fast he's tricky to control when precision becomes necessary. Meanwhile, other players are finding that thanks to poor GPU and CPU utilization they're getting poor performance on PCs that should be able to run it much better.
Thankfully, the modding and tweaking community has already stepped in and begun repairing Replicant. First there's the Special K injectable by old mate Kaldaien, which will let you get rid of the mouse cursor showing up when you're playing with gamepad, cut down on stuttering by disabling the PS4 HID input, set your own framerate limit, and turn off the internal v-sync. Then there's the Nier Replicant High FPS Fix, one of the first things for the game available on its brand new Nexusmods section. It'll let you run Nier Replicant over 60 fps without borking the animations—except for when you're slow-walking, which might leave you facing the wrong way.
Of course, you could just wait for publisher Square Enix to patch Nier Replicant. After all, it only took a measly four years for an upgrade patch for Nier Automata to be announced.