Have you read this article ?
Joël Deligne gives more informations on his Artstation :
"It is a converter of 3D animations read in 3Ds max to a 2D animation readable in the Spine software made with MaxPlus Python API and PyQt.
The principle is to select the bones that you want to keep as well as the animations that accompany the skeleton in 3D, set up a camera for the desired projection angle and then just let the tool create a JSON file that can be easily imported into Spine.
The skeleton is recreated in 2D by calculating the distances between each vector corresponding to the root of the bones.
Then the angle and the translation of these bones are recalculated frames by frames to recompose the original animation."
>>> Is there some developers here how are able to create such a tool for the comunity ?
NB: Esoteric could create a dev challenge with little prizes to ask dev of the comunity to create some tools and plugins wich could help a lot all the users of Spine 2D in different ways (conversion between 2D file formats, etc)
I see that the idea to use 3D motions to create more 2D animations is something in the air. What do you think ?