Pokemon Unite allows players to team-up with their friends, but adding friends isn't exactly intuitive. The new MOBA-style Pokemon game centers on 5v5 matches. While you can enter a Ranked or Random battle with any group of random teammates, many players find it easier to play with people they know. Pokemon Unite does have the option to play with friends, but you'll have to do a bit of work to add friends.
There are actually three ways to add friends in Pokemon Unite. Two of those ways can be accessed through the Friend Screen, which can be accessed by pushing "X" and then scrolling down to the Friends option. From the Friends Screen, you can search for Friends via the "Friend Search" sub-menu. You can then search for Friends via Trainer Code or by pressing the "-" button to add your Nintendo Switch account friends. Alternatively, you can add friends after a match by highlighting their name on the screen after a match, pressing "A" and then hitting the "Add Friend" to send a request.
Once you've added friends to Pokemon Unite, you can invite them to your party by pressing Y while in the lobby for a battle and then selecting players. If they accept the request, you'll be able to play in Pokemon Unite matches together. You can also give a friend your Lobby ID (or enter someone else's Lobby ID) to enter a lobby with your friends via the Lobby Search function. When you enter a match, the unfilled Lobby slots will be filled by random players unless you select "Friends Only" when entering a match. You can also use Pokemon Unite's in-game text chat with your friends after you've played at least five matches.
Keep in mind that you need the Trainer ID code in order to add friends within the game. You can find your Trainer ID by pressing the "L" button to pull up your Trainer Info. You can't search for friends via their Trainer Name - you can only search by Trainer ID.
Pokemon Unite is available now on the Nintendo Switch. A mobile version will be released later this year.