It looks like the default UE4 sphere is very highpoly, yet not hurting the performance so much.
How comes that possible?
smooth shading. It isn’t that high poly, but it uses vertex normals interpolated across surfaces rather than surface normals. Just hit “smooth shading” in whatever 3d modeling software you are using, then try importing it into ue4. In blender the smooth shading button is on the left toolbar in object mode, but I don’t know about 3ds max or Maya.