How to customize collision system using BP?

I have a question in general, perhaps someone has an idea.
Do you know The Settlers series? Mainly parts 3 and 4. I was wondering what would be the least taxing way to implement “territory”. In The Settlers (3,4) towers were claiming territory (and one unit type could expand territory as well, but that’s a little bit more complicated for now).
Currently I just spawn small cylinders to indicate territory, however I’m struggling to make it work in “backend”, meaning: make territory work and let it AND (logical operation) with itself (additive territory). The second part would be making so that Player 1 territory can’t override Player 2 territory. One of ideas proposed to me would be to create hidden grid that serves purpose of storing territory information. I wonder if there is an easier way. I’ve tried with collisions, but perhaps I’ve messed something up, as it was returning location (0,0) of collision. Is there a way to find all (or few) common points of two colliding spheres/cylinders/capsules without doing a lot of customizing? Do I need to go with C++ instead of Blueprints?