Given how the hism(s) work that makes no sense.
If you loop or find the index to be able to change the scale to 0,0,0,
You may as well replace the instance entirely. Or simply remove the instance.
The box idea to do the loading manually has something to it, what it’s missing though is that you would have to somehow partition the hism from being just one, to being one per box area. And you’d probably need to parse a manual merge actors on it to get it to behave as a single drawcall from a distance.
Since the foliage tool just does that, way better than this simplistic system (I belive they use octree for it because it takes Z into account - could be wrong as I haven’t cracked the source open on it yet) I simply don’t see a reason to waste time concocting it manually…