Firstly, this is to help my friend because I have no Pokemon game [oooooooof]. But anyway, my friends need to know and they don't use this site [they could search it up but they always ask me because out of all of them I know the most about Pokemon lol]. anyway pls answer.
The current legendary distribution is Entei for Sun or Ultra Sun and Raikou for Moon and Ultra Moon. As for UK/Ireland, these Pokémon are available via Nintendo Network 4-25 this month.
How to get Raikou or Entei Open your Pokémon Sun, Pokémon Moon, Pokémon Ultra Sun or Pokémon Ultra Moon game. Select Mystery Gift on the main menu. Select Receive Gift. Select Get via Internet, then Yes to connect to the internet. Watch as you receive your Pokémon! Resume the game, make sure you have an empty space in your party, and speak to the delivery person in any Pokémon Center to receive your Pokémon! Be sure to save your game!
Source