So far 1 real one (Sonic the Hedgehog: The Movie, sometimes referred to as the "Sonic OVA"). But there's this youtuber called "SonicMovies", who makes sonic movies from sonic games. Also, Blue Core Studios is making a non-profit Sonic Fan Film which may come out this year. But other then that, so far, 1.

There's sonic riders, one about Princess Elise and Sonic: The Movie that's the only three I have seen.

Season 1:

Episode 1:

Japanese title - Chaos Control Freaks.

American title - A Supersonic Hero Appears

Episode 2:

Japanese title - Infiltrate! Area 99!

American title - Escape from Area 99!

Episode 3:

Japanese title - Dr. Eggman's Ambition.

American title - Dr. Eggman's Ambition.

Episode 4:

Japanese title - Get the Chaos Emerald.

American title - Get the Chaos Emerald.

Episode 5:

Japanese title - Clash! Sonic vs. Knuckles.

American title - Sonic vs. Knuckles.

Episode 6:

Japanese title - Fierce Battle! School Wars!.

American title - I want to be respected!

Episode 7:

Japanese title - Giant Free For All at Chris' House Party!

American title - Cream and the Flower Crown.

Episode 8:

Japanese title - Emergency Launch! X-Tornado!.

American title - Dispatch Tornado #2.

Episode 9:

Title for both - Amy on the Beach.

Episode 10:

Japanese title - Fierce Fight! Sonic Baseball Team!.

American title - Chaos Emerald, Battle at the Baseball Field.

Episode 11:

Japanese title - The Beautiful, Mysterious Thief Rouge!.

American title - Rouge, Beautiful Thief!

Episode 12:

Japanese title - Before the Attack on Eggman's Base.

American title - All out attack on Eggman's Base Part 1.

Episode 13:

Japanese title - After the Attack on Eggman's Base.

American title - All out Attack on Eggman's Base, Part 2.

Episode 14:

Japanese title - Chase After the Hero, Sonic!.

American title - Cream and Cheese.

Episode 15:

Japanese title - Raid of Egg Fort the Flying Fortress!

American title - Skirmish in the Sky.

Episode 16:

Japanese title - Aim for It! The Sunken Ship in the Southern Seas.

American title - Depths of Danger.

Episode 17:

Japanese title - Knuckles! Clenched Fists of Anger.

American title - The Adventure of Knuckles and Hawk.

Episode 18:

Japanese title - Huge Battle on the Savannah!

American title - The Dam Scam.

Episode 19:

Japanese title - Ghost of the Old Castle, King Boom Boo.

American title - Scream Test.

Episode 20:

Japanese title - Departure, Egg Fort II.

American title - Cruise Blues.

Episode 21:

Japanese title - Speed Match! Sonic vs. Sam.

American title - Fast Friends.

Episode 22:

Japanese title - Summer Vacation - Chao~ An Observation Diary.

American title - Little Chao Lost.

Episode 23:

Japanese title - Mayhem! The 6th Chaos Emerald.

American title - Emerald Anniversary.

Episode 24:

Japanese title - Wild Sonic! Strategic Capture Operation.

American title - How to Catch a Hedgehog.

Episode 25:

Japanese title - The Last Chaos Emerald.

American title - A Dastardly Deed.

Episode 26:

Japanese title - Birth! Super Sonic.

American title - Countdown to Chaos.

Season 2:

Episode 27:

Japanese title - The Beginning of the Disaster.

American title - Pure Chaos.

Episode 28:

Japanese title - The Mysterious Liquid Life-form, Chaos.

American title - A Chaotic Day.

Episode 29:

Japanese title - Amy the Captive.

American title - A Robot Rebels.

Episode 30:

Japanese title - Egg Carrier Battle.

American title - Heads Up Tails.

Episode 31:

Japanese title - Gamma the Wanderer.

American title - Revenge of the Robot.

Episode 32:

Japanese title - The Scream of Perfect Chaos.

American title - Flood Fight.

Episode 33:

Japanese title: The Puzzle of Project Shadow.

American title - Project Shadow.

Episode 34:

Japanese title - Sonic the Fugitive.

American title - Shadow Knows.

Episode 35:

Japanese title - Escape from Prison Island.

American title - Sonic's Big Break.

Episode 36:

Japanese title - A Threat From Outer Space.

American title - Shadow World.

Episode 37:

Japanese title - The Battle of the Space Colony, Ark.

American title - Robotnik's Revenge.

Episode 38:

Japanese title - Maria's Request, Everyone's Request.

American title - Showdown in Space.

Episode 39:

Japanese title - Chaotix Detective Agency.

American title - Defective Detectives.

Episode 40:

Japanese title - Eggman inc.

American title - Sunblock Solution.

Episode 41:

Japanese title - The Light is Ours.

American title - Eggman for President.

Episode 42:

Japanese title - Amy, Love's Escape Journey.

American title - A Date to Forget.

Episode 43:

Japanese title - Huge Home Electronics Panic.

American title - Mean Machine.

Episode 44:

Japanese title - The Ridiculous Epic Spy Battle.

American title - The Sewer Search.

Episode 45:

Japanese title - Sonic Battle - Opening.

American Title - Prize Fights.

Episode 46:

Japanese title - Sonic Battle - Final.

American title - A Wild Win.

Episode 47:

Japanese title - Decisive Battle on the Equator.

American title - Map of Mayhem.

Episode 48:

Japanese title - Sonic vs. a Monster from Underground.

American title - The Volcanic Venture.

Episode 49:

Japanese title - The Day the Earth Stood Still.

American title - The Beginning of the End.

Episode 50:

Japanese title - Morning of Farewells.

American title - Running Out of Time.

Episode 51:

Japanese title - Chris' Long Journey.

American title - Friends 'Til the End.

Episode 52:

Japanese title - Memories of the Wind.

American title - A New Start.

Season 3 (Final Season):

Episode 53:

Japanese title - A Messenger from a Meteor Shower.

American title - A Cosmic Call.

Episode 54:

Japanese title - The Spaceship Blue Typhoon.

American title - Cosmic Crisis.

Episode 55:

Japanese title - The Water Planet Hydo.

American title - H2 Whoa.

Episode 56:

Japanese title - Dr. Eggman Appears.

American title - An Enemy in Need.

Episode 57:

Japanese title - The Battle of the Ice Palace.

American title - A Chilling Discovery.

Episode 58:

Japanese title - The Girls' Jungle Trap.

American title - Desperately Seeking Sonic.

Episode 59:

Japanese title - Chaotix Go Into Space.

American title - Galactic Gumshoes.

Episode 60:

Japanese title - Shadow's Rebirth.

American title - Trick Sand.

Episode 61:

Japanese title - The Metarex battleship Invades.

American title - Ship of Doom.

Episode 62:

Japanese title - Secret of the Underground Canyon.

American title - An Underground Odyssey.

Episode 63:

Japanese title - Fort in Space - Metal Planet.

American title - Station Break-In.

Episode 64:

Japanese title - Clash! Sonic vs. Shadow.

American title - A Metarex Melee.

Episode 65:

Japanese title - Chaotix' Electric Love Shock Tactics.

American title - Mission: Match-Up.

Episode 66:

Japanese title - Crossing the Galaxy Corridor.

American title - Clash in the Cloister.

Episode 67:

Japanese title - the Black Trap.

American title - Testing Time.

Episode 68:

Japanese title - Above a Destroyed Planet.

American title - A Revolutionary Tale.

Episode 69:

Japanese title - Please, Marmolin.

American title - The Planet of Misfortune.

Episode 70:

Japanese title - The Eggman Armada Appears.

American title - terror on the Typhoon.

Episode 71:

Japanese title - Cafe Chaotix.

American title - Hedgehog Hunt.

Episode 72:

Japanese title - The True Form of the Metarex.

American title - Zelkova Strikes Back.

Episode 73:

Japanese title - Shadow the Assassin.

American title - The Cosmo Conspiracy.

French title - What's Happening to Shadow?

Episode 74:

Japanese title - The Lost Planet.

American title - Eye Spy.

Episode 75:

Japanese title - The Day of Plantations.

American title - Agent of Mischief.

Episode 76:

Japanese title - Battle! Dark Oak.

American title - The Light in the Darkness.

Episode 77:

Japanese title - What I Can Do For You?

American title - A Fearless Friend.

Episode 78:

Japanese title - The Place where Planets are Born.

American title - So Long Sonic.