Elite TM Pokémon Go is an extraordinarily rare item you can get as a reward for achieving a high rank in the Pokémon Go Battle League.
Elite TM Pokémon Go: How to Get
The Elite TM is awarded to anyone who reaches Rank 7 before the end of the first season on May 1. The Elite TM is a special TM that lets you change and choose the move your Pokémon learns. What makes the Elite TM so special is that you can even teach Pokémon event exclusive moves, such as those found during Raid and Community Days.
With the Elite TM, you don't need to re-catch and train new Pokémon of ones you already have. If in the future your favorite Pokémon gets a new move, you can use the Elite TM to teach them that move rather than catching another and replacing it.
The Battle League will be conducted in Leagues, with the Great League on March 13. Each league will run for two weeks, and the last two weeks will feature all three Leagues playable.