Black Jack

Tetsuwan Atom aka Astro Boy
Appeared in episode 27 of the 1980 (second) series.

Phoenix 2772
Appeared as a prison warden.

Bandar Book
Appeared as a space priate similar to Captain Harlock

Kaminomi
Episode needed

Ribon no Kishi aka Princess Knight
Episode 3 of the 2003 4-part series "Black Jack: The 4 Miracles of Life" features Princess Sapphire