Wave Mail appears in 3 version groups since Generation III, an All mail item in the Mail pocket
PokéAPI item 520 of 2,223, All mail category, Mail pocket
Effect, in PokéAPI's words
Wave Mail: “Lets a Trainer write a message and send it via Pokémon trade.”
Wave Mail shares its longer effect text with 35 other All mail items; it is quoted once on the category page. All mail
Games
Wave Mail is listed in the text of 3 version groups, first in Generation III
Game index by generation
IIIIIIIVVVIVIIVIIIIX
Named in
Ruby and SapphireEmeraldFireRed and LeafGreen