Hi,
I seem to remember I saw something like that a long time ago. This would be extremely helpful in preventing accidentally going online with mods. Would be a nerve wracking mod to test though 
btw, if you have all your mods installed in the separate mods folder, renaming dinput8.dll should be enough to disable all mods and go online safely right ?
So I made a copy of my vanilla, not even started up yet, Steam GTA V gamefoder :
C:\Games\Grand Theft Auto V - Mod\
As to keep the original steam folder 100% clean and for online use
So when I tried to mod the "C:\Games\Grand Theft Auto V - Mod" copy it never worked.
Only when I tampered with the GTA V in the steam folder I got ScriptHook & trainer to work..
is this a known thing ?