In Pokémon Scarlet and Pokémon Violet, you can trade and battle with Trainers all over the world by using a feature called the Poké Portal.
Use the Nintendo Switch system’s local wireless to connect with people nearby or use an internet connection to interact with people from all over the world.

Enjoy co-op play with the Union Circle!

Your adventure is bound to be more enjoyable by playing with friends, cooperating to beat Tera Pokémon in Tera Raid Battles, and sometimes even testing your skills against each other.
Additionally, with the new Union Circle feature added to the Poké Portal, you and up to three friends can adventure together in the same space, cheering each other on as you battle wild Pokémon or showing each other the Pokémon that walk along with you.
There is no single way to play using the Union Circle. You can wander around together and spend time with your friends how you want to!

Trade Pokémon with each other

In the Poké Portal, there are two features that allow you to enjoy trading, Link Trades and Surprise Trades. A Link Trade lets you trade with a specific person. With a Surprise Trade, after choosing a Pokémon to trade, you’ll be able to trade with a random Trainer somewhere in the world.
Make lots of trades to find your favorite Pokémon and complete the Pokédex!

battle together

If you go to the Link Battle option in the Poké Portal, you’ll be able to have Pokémon battles with other Pokémon Trainers.
There are many battle formats. Hone your skills in Pokémon battles with Trainers from all around the world, using the Pokémon you trained!