Allow setting the same flag to different values for more than one group

### The Problem

I want region owners to be able to blacklist certain players from entering, if they wish. Right now, it's not [possible](https://worldguard.enginehub.org/en/latest/regions/flags/#region-groups) to set the same flag to different values for more than one group. Which means the only option is to deny nonmembers from entering, where members are added as a whitelist. But I don't want that, I want a blacklist.

### A Solution

One option is to allow owners and nonmembers to enter, but members to not enter. Then adding members turns into a blacklist. But if I deny entry to members now, the owner can't enter either. I want to be able to set different values for the entry flag for owners vs members.

Is there a way to let us set different values? I'm assuming there is a reason if not, so I'm curious.

### Alternatives

A flag to deny entry to specific people. GPFlags allows for this but it connects to claims in the Grief Prevention plugin. I need to use regions, not claims.

### Anything Else?

_No response_