FlansBulletProtect is a minecraft plugin that prevent player from shooting from spawn on players in outside

Dependency:

WorldGuard 6.1 (plugin) FlansModAPI-v1.3 (mod)

How its work:

Install WorldGuard 6.1 and FlansModAPI-v1.3
Launch your thermos/mohist server
Create a new region called "spawn" with the command /rg define spawn
Player on spawn will now, not being able to deal damage with weapon on player located outside spawn

if you got any question feel free to contact me on discord: chapyy or Chapy#0001