The Crown Tundra DLC for Pokémon Sword and Pokémon Shield has a couple of version exclusives, including Legendary Pokémon. Don’t worry! Due to the online play of Sword and Shield, a random player or a friend can help you get the Legendary Pokémon not native to your game. On top of that, you can remember up to three encounters, meaning you can save a Pokémon (even not found in your game normally) and hunt it anytime you want or host it yourself!