Quick answer — Yoshiki Tanaka worked on Legend of the Galactic Heroes (Original Creator), Legend of the Galactic Heroes: Die Neue These - Collision (Original Creator), Legend of the Galactic Heroes: Die Neue These Second (Original Story) and 7 more anime.
Yoshiki Tanaka worked on Legend of the Galactic Heroes (Original Creator), Legend of the Galactic Heroes: Die Neue These - Collision (Original Creator), Legend of the Galactic Heroes: Die Neue These Second (Original Story), Legend of the Galactic Heroes Gaiden: A Hundred Billion Stars (Original Creator), Legend of the Galactic Heroes: Overture to a New War (Original Creator), Legend of the Galactic Heroes Gaiden: Spiral Labyrinth (Original Creator), Legend of the Galactic Heroes: My Conquest Is the Sea of Stars (Original Creator), Legend of the Galactic Heroes: Die Neue These (Original Creator) and 2 more.