About the Free Vectary version! :)

In fact I found a trick ! ;)

Go there : https://github.com/ksons/gltf-blender-importer
and install it inside Blender (allways a nightmare to ...navigate in menus for install Addon but... :)
You can now import your glTF/ GLB
and make any what you want with it! :)

So Vectary (free) --> Blender (free) --> Moi3D :)

glTF/ GLB --> OBJ --> with _ImportOBj by Max Smirnov --> 3DM :)