Except you're not using the sewing machine to design anything. The design is already done; you're just making physical prototypes of something already designed because nobody has time/inclination to learn Blender.
I'm just rather sick of misleading "clickbait" titles on HN.
I'm a bit confused here, what design is already done? The designs for the characters? Nope, those are literally coming to life through the sewing machine first. There weren't any sketches prior. How would 3D help this?
Why not just use photos of the dolls and skip turning them into sprites altogether?
Actually, they are being used as is. That iPad screen shot is a bit misleading. Our artist did up the little guys in illustrator while we were figuring out how we want these things to animate on screen.