It really annoys me how a very small amount of the Mario Maker costumes just have a random appearance listed instead of their debut. You know what? I'm gonna fix the inaccurate ones
Mario: Donkey Kong
Luigi: Mario Bros.
Trampoline: Donkey Kong Jr.
Mario (Silver): Super Mario 64
Mario (Gold): New Super Mario Bros. 2
Shy Guy: Yume Kojo: Doki Doki Panic (same for Birdo)
Wario: Super Mario Land 2: The Six Golden Coins
Donkey Kong: Donkey Kong Country
Mr. Game & Watch: Ball
Arwing: Starwing
Toadette: Mario Kart: Double Dash!!
Shaun the Sheep: A Close Shave
Undodog: Mario Paint
Mario: Donkey Kong
Luigi: Mario Bros.
Trampoline: Donkey Kong Jr.
Mario (Silver): Super Mario 64
Mario (Gold): New Super Mario Bros. 2
Shy Guy: Yume Kojo: Doki Doki Panic (same for Birdo)
Wario: Super Mario Land 2: The Six Golden Coins
Donkey Kong: Donkey Kong Country
Mr. Game & Watch: Ball
Arwing: Starwing
Toadette: Mario Kart: Double Dash!!
Shaun the Sheep: A Close Shave
Undodog: Mario Paint