Creative Common license?
I've noticed that on other mod sites like Nexus and Gamebanana, mod authors are able to state permission terms that denotes what others may or may not do to their mod with or without their permission. In the case of Gamebanana, this goes slightly further by having mods be protected under a CC BY-NC-ND 4.0 license by default unless stated otherwise by the author.
Do 5mods have something similar to this, or is this something that mod authors themselves have to decide by their own?
Since 90% of peds mods are converted off games and 99% of cars are also conversions off games (Forza, Assetto, etc) and 99% of maps are conversions, how do you assign a license to something that is really the IP of a gaming company? How would you enforce it? Just because you have the skills to convert Rick Grimes or Lara Croft or Claire Redfield or Liberty City doesn't make it yours. If you believe it does you're in for a big legal surprise. You will be IP woke.
As for xml mods, the modders should face criminal prosecution because the rancid garbage they upload is indeed a crime. Particularly clothes for the MP she-male. Of course that's just my opinion and it's definitely not shared by the rest of the community, nor endorsed by this site, nor by its parent sites and its shareholders.
Strictly speaking, you can't mod GTA 5 if in any way it involves reverse engineering. That means SH5 and OpenIV would likely fall under that umbrella but R* tolerates it.
So the whole asking for permission is BS.