hello there, i am too having the same issue where i want to voxelize a certain portion of a part, currently this is what i have:
now i haven’t been able to find anything that would allow me to voxelize a small portion of a block, therefore the optimization on my voxel destruction is not good as it voxelizes the entire block and then greedy meshes it.
as for the info i have for you, i recommend using greedy meshing.
Try quadtree partioning. I haven’t actually made anything voxel destruction yet, but I came across quadtrees when I was looking for the best way to do things. Here is a post I found. Voxelization using Quadtree Partitioning