Ducklett makes its debut to Pokémon Go during the Pokémon Go Fest 2020 weekly challenges, and you can find it in the wild. You should be able to find it by wandering around your neighborhood, or by hatching 5-kilometer eggs. When you capture enough of them, you can evolve it into Swanna. It can learn several different moves, but you want to make sure you keep one with the best choices.
Swanna is a Water and Flying-type Pokémon. It will have a maximum CP of 2,088 and an attack of 182, a defense of 132, and a stamina of 181. Unfortunately, due to its CP, you likely won’t want to use it in the Ultra League, but it could be a viable option for the Great League if you don’t attempt to power it up beyond 1,500 CP. It’s only to Electric and Rock-type attacks, which could give it a small advantage when you think about your roster. You wouldn’t want to have Swanna as your first Pokémon, but it’d be a good reserve choice that you could rotate in after the first fight.
The best moveset available to Swanna include water gun and bubble beam, or water gun and hurricane. The first option has it using two Water-type attacks that are good if you primarily want to use Swanna as a way to counter Ground, Rock, and Fire. But because it’s also a Flying-type, you should optimize on the full benefits of its status-type bonus attack moves, so water gun and hurricane are better combo. The water gun and bubble beam combo would work exceptionally well for lower-level raids.