About plotting sets in 3D, I’ve used Makie + Polyhedra (that’s what LazySets.plot3d boils down to, after computing the constraint representation of the set). It is of course easier to just plot a set of points in 3D (you can use Plots). I saw your similar question in Error using LazySets.plot3d - #3 by adropintheriver and I presume the problem is related to package versions installed.