The Sword & Shield Pokemon Center Limited Special Set with the exclusive HOPPE DAISHŪGO (Mouse Pokémon) TCG merchandise, has officially been discontinued before it's release. It would have been released on January 1, 2020.
A quality issue was the main reason for this cancellation. The exact reason that caused this quality issue, is unknown.
This was stated on their official website, including an apology from Pokémon. It's also unknown if this product will ever release again.