2.8 makes problems exporting to 3ds.
I am a big fan of the Blender 2.8 texture mapping tools. But I think you are right about not being able to create Isadora compatible 3ds files directly out of Blender. I use Cheetah 3D and MeshLab to condition the forms I make in Blender for use in Isadora. But it is still a better modelling and texturing experience to start the process using Blender 2.8.