@vortigaunt4 I hope I’m not to late, but if you haven’t figured it out yet: You could export the scene as an Alembic-file, but you could also copy and past (most times) your object from Blender 2.8 to Blender 2.79b and upload your scene from there with the sketchfab plugin.
- Just select all objects in Blender 2.8 (I don’t know if you should select the lamp and the camera. I’ve not tried that)
- Press CTRL-C
- Start an Blender 2.79 (if you haven’t already)
- Press CTRL-V, and probably the scene will copy.
- You most likely have to add new camera’s and lights if you want to, but then again, I don’t think you need them for sketchfab.