Vacuum between submeshes in scaling

i divided a sphere into 2 parts using blender and exported it.
then i imported it and the submeshes array had 2 different meshes.
i scaled one mesh on the x axis, how can i merge them together so i can fill the space between them.

If I have a question I search in google with this tokens first: “babylon js merge mesh”
and I get in most of the case a speed answer like this one