Here is another test of another small script uploaded as part of my "Global Weapons Modifiers" project (https://github.com/David-Lor/GTAV-GlobalWeaponsModifiers). In this case, ALL PEDS are UNARMED, which means, Fist Fight!
The Peds Without Fear mod is recommended if you experience peds fleeing from combat, specially during SP missions.
My mod: https://raw.githubusercontent.com/David-Lor/GTAV-GlobalWeaponsModifiers/master/AllPedsUnarmed.cs
Installation of My mod: right click: save as: save into Grand Theft Auto V/scripts folder (ScriptHookV & ScriptHookV DotNet required!)
Peds Without Fear mod: https://www.gta5-mods.com/misc/peds-without-fear