Here is an overview of the game, via The Pokemon Company:
The Pokemon Sword and Pokemon Shield games take place in the Galar region. Galar is an expansive region with diverse environments— an idyllic countryside, contemporary cities, thick forest, and craggy, snow-covered mountains. The people and the Pokemon who live there work together closely to develop the industries in the region. Fans will have the opportunity to visit various Gyms in the Galar region in their quest to become Champion. They will not be alone, since the newly discovered Pokemon they choose to be their first partner will be by their side.
“Pokemon Sword and Pokemon Shield are the latest exciting adventures in the Pokemon video game journey that began twenty-three years ago on this day,” said Mr. Ishihara. “Since then, Trainers around the world have discovered new Pokemon, engaged in epic battles, and made countless memories along the way. We look forward to continuing this journey by exploring a stunning new region in the Pokemon universe when the games launch later this year on Nintendo Switch.”
■ Starter Pokemon
The adventure begins in Pokemon Sword and Pokemon Shield when players choose one of three new Pokemon–Grookey, Scorbunny, or Sobble.
A mischievous chimp Pokemon that is full of boundless curiosity.
A rabbit Pokemon that is always running about, bursting with energy.
A somewhat timid lizard Pokemon that shoots out attacks as it hides itself in the water.