Unfortunately there isn’t. It’s not something you can do easily, especially not in blueprints.
Array bounds is a simple operation simply getting the highest and lowest coordinates and creating a box that encompasses them.
What you want would be something much much more complex.
If you tell me what specifically you’re trying to do, I’m positive I can find a much simpler solution.
From the names of the blueprints, it seems you’re making a city-builder type game. Are you trying to create that collider to know which town the player is clicking on or something like that?
I thought of that, but if this is a city builder, the city won’t always necessarily be circle-ish. You can already see what looks to be the castle is off-center.