Pokemon Sword and Shield has offered players a viable alternative to trading to collect most of the game's various version-exclusive Pokemon. There are about 40 Pokemon in Pokemon Sword and Shield that are exclusive to one version of the game or another. Some of these Pokemon are new Pokemon like Cursola or Sirfetch'd, while others are existing Pokemon species like Tyranitar or Braviary. While it used to be easy to collect various version-exclusive Pokemon using the Global Trade System, Pokemon Sword and Shield did away with that online feature and replaced it with the far inferior Y-Comm system. However, players don't necessarily need to trade with another player to collect Pokemon exclusive to either Pokemon Sword or Pokemon Shield - they simply need to have access to the Internet.
The key to collecting various version-exclusive Pokemon is to participate in public Max Raid Battles. These 4-person battles take place in the Wild Area and include tons of wild Pokemon, including species that are exclusive to one Pokemon game. While you might only be able to find a Tyranitar Max Raid Battle in Pokemon Shield, you can still access that raid via the Internet from either game.
In order to find these raids, you'll need to turn on your Y-Comm by pushing the Y button and then connecting to the Internet by pushing the + button. From there, you can search for "Seeking" stickers, which indicate that players are looking for partners to take on various Max Raid Battles. While finding various Max Raid Battles isn't always easy - the Y-Comm function often sends players to raids that have either already filled up or have started - you should be able to find most of the version exclusive Pokemon if you're patient enough.
Players can also obtain many Pokemon that can only be evolved through trading - such as Machamp or Gengar - by participating in Max Raid Battles. Some of these Pokemon can also be found in the Wild Area at random.
Let us know how your Max Raid Battles are coming along in the comment section, or find me on Twitter at @CHofferCBus to talk all things Pokemon.