This appears to be a reference to a bootleg or ROM hack rather than an official Nintendo release. Here’s why:
If you are looking to share this specific file or your experience with it, here is a post you can use: 🎮 Diving back into Hoenn with a classic! Just picked up the 1986 - Pokemon Emerald (U)(Trashman)
The franchise has expanded to include anime series, manga, trading card games, and movies. Pokémon has become a cultural phenomenon, with a global community of fans who share a passion for the series. 1986 pokemon emerald %28u%29%28trash man
Access Cheat Menu: Go to Tools > Cheats (mGBA) or Cheats > Cheat list (VBA).
assigned by the Scene (a global network of groups who rip and share games). It does refer to the year 1986; Pokémon Emerald was actually released in 2004/2005. Pokémon Emerald (U) signifies that this is the USA/North American version of the game. : This is the handle of the ROM dumper This appears to be a reference to a
Core Mechanics: It features double battles, animated Pokémon sprites at the start of encounters, and the ability to catch Pokémon from both the Ruby and Sapphire versions. Distinction from "Trashlocke"
I think there may be a small issue here. Pokémon Emerald was not released in 1986, and it's not clear what "(u)" and "(trash man)" refer to. Pokémon Emerald was actually released in 2005 for the Game Boy Advance. Rattata → Trashata Koffing → Dumpstering Muk →
While "1986" might look like a release year, it is actually the scene release number