The term equivalent trade glitch Pokémon refers to any one of two or more Glitch Pokémon which share the same hexadecimal identifier. 'M for example, when transferred to Pokémon Yellow will become 3TrainerPoké; meaning 3TrainerPoké is an equivalent trade Glitch Pokémon of 'M (00) and 'M is an equivalent trade Glitch Pokémon of 3TrainerPoké.
Between games such as Red/Blue->Yellow, Red/Green->Blue and Red/Green-> Yellow, equivalent trade glitch Pokémon are often completely different, due to changes in the game code.
Trading a glitch Pokémon from one version to another is an ideal way of obtaining certain glitch Pokémon.
Examples of where equivalent trading is useful
1. 3TrainerPoké (hex:00) in Pokémon Yellow can easily be obtained by trading an 'M (00) over from Pokémon Red and Blue. 'M can easily be caught on Pokémon Red and Blue via the Old Man Trick, while 3TrainerPoké is harder to obtain without trading in Pokémon Yellow, as the large storage box byte shift glitch or Johto guard glitch, or possibly arbitrary code execution must be used.
2. As Red/Blue's PokéWTrainer (index number 196) always freezes the game on the opponent's side, the Ditto Trick cannot be used to obtain it. In Pokémon Yellow, X ゥ- xゥ, has the same index number and does not freeze the game on the opponent's side, so the player can obtain it with the Ditto Trick and trade it over to Red/Blue to obtain PokéWTrainer.
3. 'M (FF) can be obtained with CoolTrainer, LOL glitch, Rival LOL glitch, however trading a Q from Pokémon Yellow on to Pokémon Red and Blue (which evolves from the Trainer escape glitch obtainable glitch Pokémon 4 4 Hy (with 192 Special) at level 6) is a good method of obtaining one, and used to be known as a means of obtaining one before the aforementioned data copy tricks were discovered.