Elmo's Letter Adventure (Toon Disney/Jetix)

As a cel animated home video, here is a crossover using characters from Toon Disney and Jetix, two sides in one.

Plot

 * Elmo is joined by Pooh Bear and Tigger, Kion, Timon and Pumbaa, CatDog, Heathcliff and Riff-Raff, the Hangin with the Heroes stars, Ash Ketchum, Sonic the Hedgehog, Sandra Larson, Felicia McCoy, Kirby, Wario and Penny Crygor, Tai and Kari Kamiya, Mushra, Fox McCloud, Kick the Cyber Cat, Flint Hammerhead and Mondo Ooya, as they tackle levels like Outer Space hosted by Grover, Lloyd Nebulon and Seymour the Scientist, Alphabet Farm and Orchard hosted by Big Bird, Zummi Gummi, Baloo and Kit Cloudkicker, Mikey, his older brothers, Timmy, and the Kanto Backstreet Boys, as well as Underwater hosted by Ernie, Jake Long, Milo Murphy, Kuzco, Kim Possible, Star Butterfly, Sabrina Spellman, and Misty and the Orange Crew, unaware that the mean girls and bad guys are out to get Ash and his Pikachu.

The Conductors of Shining Time Station

 * 1) Mr. Conductor 1 (Ringo Starr)
 * 2) Mr. Conductor 2 (Alec Baldwin)
 * 3) Mr. Conductor 3 (Michael Brandon)

Sesame Street Alumni

 * 1) Elmo (
 * 2) Grover (
 * 3) Big Bird (
 * 4) Ernie (

Toon Disney Alumni

 * 1) Winnie the Pooh and Tigger (
 * 2) Kion, Timon and Pumbaa (
 * 3) CatDog (
 * 4) Heathcliff and Riff-Raff (
 * 5) Darkwing Duck (
 * 6) Goliath (Keith David)
 * 7) Wildwing and Nosedive Flashblade (
 * 8) Hercules (
 * 9) Buzz Lightyear (
 * 10) Tarzan (
 * 11) Captain Crandall (Matt Hill)
 * 12) Underdog and Underpup (Tom Kenny and Max Charles)

Jetix Alumni

 * 1) Ash Ketchum and Pikachu (
 * 2) Sonic the Hedgehog (
 * 3) Sandra Larson (
 * 4) Felicia McCoy (
 * 5) Kirby (
 * 6) Wario and Penny Crygor (
 * 7) Tai Kamiya, Agumon, Kari Kamiya and Gatomon (
 * 8) Mushra (
 * 9) Fox McCloud (
 * 10) Kick the Cyber Cat (
 * 11) Flint and Rocky Hammerhead (R. Martin Klein and Ron Pardo)
 * 12) Mondo Ooya (

Friends to Grover, Big Bird and Ernie

 * 1) Lloyd Nebulon (
 * 2) Zummi Gummi, Baloo and Kit Cloudkicker (
 * 3) Jake Long, Milo Murphy, Kuzco, Kim Possible, Star Butterfly, and Sabrina Spellman (
 * 4) Seymour the Scientist (
 * 5) Mikey, Rainer, Sparky, Pyro, Timmy, A.J., Joe, Damian, Dario and Chopper (
 * 6) Misty, Cissy, Danny, Rudy, Luana and Drake (

Mean Girls and Bad Guys Alike

 * 1) Bonnie Rockwaller (
 * 2) Brittney Wong (
 * 3) Gem Stone (Jessica DiCicco)
 * 4) Fiona Von Steig (Maggie Blue O'Hara)
 * 5) Sierra McCool (
 * 6) Kendall Perkins (
 * 7) Pacifica Northwest (
 * 8) Marina Barton (
 * 9) Heather Hogwarsh (
 * 10) Jody Priscilla (
 * 11) Jordin Hanson (
 * 12) Josie Caldwell (Laura Summer)
 * 13) Vivian Goodwin and Brianna Flowers (
 * 14) Abigail Thompson (Wendee Lee)
 * 15) Jessie, James, Meowth and Wobbuffet (
 * 16) Prince Ludwig Von Monsterstein Eccentro, Batch, Gluko and Impy (
 * 17) Cliff, Lube and Shriek (Tom Kenny, Carlos Alazraqui and Maria Bamford)
 * 18) Dr. Eggman (
 * 19) King Dedede and Escargoon (
 * 20) Wolf O'Donnell, Leon Powalski, Pigma Dengar, Andrew Oikonny and Panther Caroso (
 * 21) Petra Fina Dagmar, Mr. Mite and Dino Fishman (

Thomas Segments

 * 1) Thomas and The Conductor (Ringo
 * 2) A Cow On The Line (
 * 3) Gordon and The Gremlin (Alec
 * 4) James Goes Buzz, Buzz (
 * 5) The Spotless Record (Michael
 * 6) Peace and Quiet (

Script

 * (Our crossover opens with the Version 1 intro to The New Adventures of Winnie the Pooh)
 * Kidz Bop Kids: Gotta get up