Set VRAM to 4GB in BIOS. You can run the game at 120 FPS? No. The engine is hard-coded to 60 FPS. It will feel smooth, but you cannot exceed that cap.
If you prefer a plug-and-play experience without emulators, the later entries in the series were built specifically for PC and are available on the Steam Store One Piece: Pirate Warriors 3 one piece pirate warriors 2 pc requirements new
Related search suggestions (terms you can use for further lookup): Set VRAM to 4GB in BIOS
If you were looking for the most current PC game in the series, it has higher requirements due to recent DLC and engine updates: one piece pirate warriors 2 pc requirements new