Using silent aim in multiplayer is highly discouraged due to several risks: VAC Detection : Modern anti-cheat systems like Valve Anti-Cheat (VAC) look for injected code or modified game files. Manual Bans
If you are playing offline with bots, you can experiment with built-in "legal" cheats via the console (~):
Ask the player to aim at a specific texture on the wall and shoot. If they hit the texture but the bullet hole appears 20 feet to the left? That’s desync. That is Silent Aim.
Watch how some players showcase different aim hacks in action to understand their visual behavior:
He reached for the mouse, hovering over the "End" key to toggle the menu. He realized that in a game about precision, the most silent thing wasn't his aim—it was the disappearance of his own talent.