NPC spawn tool request

As you may know, there are various npc groups/npc spawn menus, however I wonder if it was possible so that npc’s spawn within a specified radius? Much like in hammer where you can use triggers to spawn npc’s, could someone create a tool where a chosen radius can be set. Most importantly, the amount of the A.I. and weapons (possible accuracy differentiation would be nice) When the player reaches and enters the circumference of the circle it will trigger the spawning.

I know that with npc spawners you can use numpads/wire it up, but doing this is limited and monotonous- you also know where the npc is spawning so you can ‘camp’. With the idea of a ‘spawning circle’ it adds more freedom, and you don’t really know where the A.I. is, or know if you triggered it.

thank you! <3