The only thing that can get you banned is using a software to mess with the game while NOT in LAN mode.
So using a software in LAN mode or using .gsc scripts with the official loading method while not in LAN mode is fine.
https://plutonium.pw/docs/anticheat/
https://forum.plutonium.pw/search?term=mod menu&in=titles&matchWords=all&categories[]=23&sortBy=relevance&sortDirection=desc&showAs=posts