The most common method for achieving this effect without an executor involves modifying the ClientAppSettings.json file. By adjusting the rate at which the client communicates with the server, players create "lag" that makes them harder to hit.
The "Roblox Da Hood Desync Script" is designed to take advantage of vulnerabilities or loopholes within the game's code to cause other players to desync or disconnect. This can be used to gain an unfair advantage, especially in PvP (player versus player) scenarios.