When I was working on things for my dollshouse, I discovered silk gauze. This lets you do cross stitch or needlepoint on a tiny scale.
I got so interested that I actually made a picture on it.
It needs a lot of magnification to work of course, but I found that once I had got used to that, it was not nearly as difficult as the finished result would suggest.
The design was an ordinary one intended for cross stitch, and came in one of those books of cross stitch designs one can buy. But it is a good number of years ago and I can no longer remember exactly where I got the design except that I think it was an American publication.
Worked like this, the teddy measures 6cm by 7cm.