A new distribution event has been revealed featuring Shiny Eternatus for Pokémon Sword and Shield. Pokémon Sword and Shield players will soon be able to visit a participating GameStop store in the U.S. to receive a Mystery Gift code to unlock the Legendary Shiny Eternatus in their game. This distribution event is currently only announced for the U.S. and will kick off as early as this week! The Shiny Eternatus distribution has also been announced for Malaysia, the Philippines and Singapore.
Source: The Pokémon Company and GameStop