On PC, there are mods (e.g., on Nexus Mods) that claim to unlock all items, including for offline use. These often require replacing game files.
If you prefer a simpler mod rather than a server emulator, the Offline Unlocks mod on Nexus Mods is the standard choice. hitman 3 unlock everything offline
In effect, you get the gear , but not the full interactive experience . On PC, there are mods (e
If you want a truly authentic experience that mimics the online servers while remaining completely local, The Peacock Project is the gold standard. What it does there are mods (e.g.