How to Get Shiny Pokemon - Pokémon Legends: Arceus
Go to Jubilife Village and it will trigger an Outbreak.
Save your game.
Travel to the location of the outbreak and catch all the Pokemons.
If you don't see any Shiny Pokemon, quit the game and try again.
After reloading your game, go to Jubilife Village before returning to the outbreak.
If you can't see the Outbreak, reload the game and try again.
Return to the area and repeat steps 2 and 3 until a Shiny appears.
If you see a Shiny in the wild, save your game before catching it.