Download the "Hitman 2: Silent Assassin Widescreen Fix" by ThirteenAG from GitHub.
Before diving into the fixes, it's worth noting why this specific title is still sought after:
Search for the game title in the Steamunlocked search bar.
Because the game engine's physics are tied to the framerate, playing at 144Hz or even 60Hz can cause NPCs to spin wildly or Agent 47 to move at light speed.