Saving, Exporting & Loading Your existing Models is on the export tab, folder icon.

Import and export icons:

File Extensions at a Glance:

There are a few choices of file type for exporting your model, at present only importing of mh 2 models is supported.
That said gltf exporting is the method of choice in mh2 currently.

Options:

There are many options and parameters for exporting of your model in Makehman 2, take your time to go through these options and
select what methods best work for your model usage post makehuman 2.