Plutonium

SmurXz
Try to repair your game

Also read the antivirus guide and update your GPU drivers

If none of this work maybe playing in windowed borderless could stop your game from crashing.

SmurXz the real question is why is LAN an issue? Either go in LAN and do injections and stuff or if you wanna play with a friend then don't go in LAN and use the methods provided by Plutonium (check the Modding section)
Note that you can play with a friend in LAN mode with softwares like Radmin VPN or Hamachi