The "glitchy" Pokémon that was seen last week on the official site has been revealed to be Sirfetch'd. It is a Galar evolution of Farfetch'd and is exclusive to Pokémon Sword version.
Sirfetch'd is pure Fighting type with the ability Steadfast. It has a signature move, Meteor Assault, which is powerful but means Sirfetch'd is unable to take action
after using it.
A video showing Sirfetch'd in action has been released: