This background character casually makes brief appearances in all three of the 1999-2001 films: Scooby-Doo and the Witch's Ghost, Scooby-Doo and the Alien Invaders and Scooby-Doo and the Cyber Chase.
Credit goes to Ryan Hollinger on YouTube for the info and these images in his video. Thanks as well to Thomas, who sent me this video and brought it to my attention! :)
~ WildwindVampire ~