Versions
WorldEdit version: Bukkit-Official(7.1.0;8e55131)
Platform version: This server is running Tuinity version git-Tuinity-"18fdc0c" (MC: 1.15.2) (Implementing API version 1.15.2-R0.1-SNAPSHOT)
WorldGuard version: WorldGuard version 7.0.2-SNAPSHOT;bf2593e

Describe the bug
I created a new world, added flags on it, including blockade of building / placing and destroying blocks. I added all the flags to global and yet players who can use worldedit on their plots (PlotSquared) can use worldedit in that region where they shouldn't be able to build anything.

To Reproduce

1. /mv create spawn normal
2. rg flag global build deny, rg flag global block-break deny, rg flag global block-place deny
3. player with worldedit perms; //pos1, //pos2, next //set 0
4. player removes spawn

Expected behavior
It should block the player's actions.

that's not an intended feature so not sure why you think it should do that.

I do not understand you. I believe it is a mistake that a player who has not been added to a region can remove buildings there because he has perms to use // set

Correct. That's not a mistake.