If you loved The Animatrix, try Kid's Story
A bridge between a film you've already seen and one most people haven't. Kid's Story has roughly 9.6× fewer votes than The Animatrix — it's a deeper cut, not a mainstream recommendation. Here's what they share, and what the second one does that the first one doesn't.
What they share
Both films are directed by Shinichiro Watanabe, and they both carry the mindfuck mood tag, and they sit in Animation / Science Fiction territory. If that's the register that drew you to The Animatrix, the second film will land in a comparable space — through a different lens.
What Kid's Story is
The Matrix if animated by way of Japanese high school anxieties. A teen skater finds himself questioned by figures who may be agents of the system. The short nails teen angst and the original trilogy's paranoid vibe.

