With this tool, you can export the static Assemblage forms to GLTF / Obj / MTL file types. To reduce file size, the materials will all be "flat" without transparency or wireframing. You can also further optimize by using the gltf-pipeline tool.
These are generic 3D forms that can be then converted to other types (i.e. FBX etc) via other tools.
Read the Information page for the Assemblage project for some examples of how these 3D assets can be utilized.