The collectible 3D models introduced in Super Smash Bros. Melee were trophies.
Trophies are detailed three-dimensional figurines representing characters, enemies, items, vehicles, objects, and other pieces of Nintendo history. Players can collect them through modes such as lottery-style trophy systems, single-player challenges, and other gameplay rewards.
The feature gave Melee an unusual museum-like quality. Instead of focusing only on fighters, its collection celebrated decades of Nintendo properties, including characters from series such as Mario, The Legend of Zelda, Metroid, Pokémon, F-Zero, and Fire Emblem. Some trophies also depict obscure or supporting characters.
The answer is sometimes confused with stickers and Spirits, but those belong to later entries or different systems. Stickers appeared in Super Smash Bros. Brawl, while Spirits became a central collectible in Super Smash Bros. Ultimate. Medals are not the series’ canonical name for Melee’s 3D collectible models.