Not all Pokémon will carry over to Pokémon Sword and Shield - Polygon

Pokémon Sword and Shield will alllow you to import Pokémon from your Pokémon Home, but only if they can be found in the Galar Region. This is for production time and gameplay balance.

The Long Road to Pokémon Legends: Arceus Led to a Much Needed Boost, by Crystar, SUPERJUMP

New Pokemon “Sword” and “Shield” Expansions Will Add Over 200 Existing Pokemon – The Geekiary

Trade In Pokemon Sword

Pokémon Sword/Shield - Confirmed Models Are Re-Used from Nintendo 3ds Games : r/NintendoSwitch

Pokémon Home guide: How to use the new Pokémon mobile and Switch app - Polygon

Pokemon Sword and Shield Appears to Reuse 3DS Models

Not All Pokémon Will Transfer to 'Sword' and 'Shield' on the Switch

Game Freak issues statement on not being able to transfer all Pokemon to Pokemon Sword and Shield : r/Games

Here's Why Pissbaby Pokémon Fans Are Boycotting 'Sword And Shield

Pokemon Home is now available, offers easy transfers to Sword and Shield

People focused way too much on the tree screenshot. This games art-style really carries this game visually imo. : r/PokemonSwordAndShield

Sirfetch'd Loves Britain's Big Leeks: 7 Cool Facts We Learned From Today's Pokemon Sword and Shield Interviews

What Pokémon Cannot be transferred from Home to Sword?