The VRC Creator Guidelines read that Worlds are not allowed to implement a ban list that will pre-emptively prevent a user from using that world. This seems insane. That would effectively mean that, for example, if someone did not want specific individuals entering their worlds, they would have to keep them private or not upload them whatsoever.
If a known user is stalking another user, what recourse do they have to keep them from entering a world other than that? Making the worlds private prevents the general public from experiencing that world, all because of one known bad actor.
Technically speaking no world is truly “private” since as long as you have the World ID you can spin up your own non-public instance. Regardless the point of the rule is that even if someone is kicked from an Instance or banned from a Group they can still make their own Instance for that specific World.
If you have an issue with someone specific that’s for VRChat Moderation to deal with via the in-client report system, not something for the forums.
I’m this particular example, Stalker is attempting to get their hands on anything User created, be it worlds, artwork, writing, lore, regardless of platform. User has already informed Stalker they are not okay with this behavior off platform.
Because of this guideline, User has no recourse to prevent this, short of making sure Stalker never obtains a world ID for any world they make.
Assuming this is serious and you have solid evidence it’s worth elevating this to https://help.vrchat.com/hc/en-us/requests/new but there’s not much this forum can do beyond suggesting that.
Realistically you can’t prevent someone from never being able to access or see anything you make on the internet in general, even if you were able to ban the user from the world, they could just create a new account. It’s something you’ll just need to accept when posting online anywhere, that or don’t post publicly online.
Best you can (and should if you haven’t yet) is block the user on whichever platforms they’re bothering you. If they do make a new account to continue bothering you, report for harassment with evidence of previous accounts.
After thinking on the issue this does indeed seem to be the only option. Only VRC Moderation would be capable of catching whether Stalker is circumventing a ban to continue to violate the right of the user to be left alone.