free Gigantamax Meowth that was offered at the launch of Pokemon Sword and Shield? Well it really was a launch-ish offer. It's coming off the table soon: very soon.
As was announced back in November; January 15 was always the end date, so be sure you grab it before then. If you still need to do it, go to the mystery gift portion of the game's menu, then get the gift online. If you don't have that functionality yet, get 30 minutes in until you hit Professor Magnolia in the story. To sum it up: it's a special old school Meowth (not the weird new Galarian bearded kind) that can transform into a Gigantamax long cat.
A lot of other stuff is going on in Pokemon Sword and Shield though. A new raid event is live, a Galarian Slowpoke is available to catch and Pokemon Home is launching soon. Game Freak is also giving us two new expansions this year, which are both part of a $30 pass.