A simplisitc demonstration of motion blur effect.
This is using 5 copies of the cube with off set keyframes, each given their own material ID in sketchfab. Each of the blurring cubes I then set with their own opacity value on sketchfab.
Its a very simple example i know but you can do this with any mesh/any type of animation, if its a detailed mesh than you would decimate/heavily optimize the blur copies as you wont see them very clearly anyway, all you need is the general shape