Read on below to learn more about the local and online multiplayer features in Super Smash Bros. Ultimate:
Local Wireless – Up to 8 players
Get together with friends and play anywhere! Up to eight players can join the fun by linking Nintendo Switch consoles.
Online play – Up to 4 players
Battle it out online! You’ll be matched according to your overall Global Smash Power, as well as your preferred rules. You can also set up a private room for online play with friends, where you’ll be able to voice chat via the Nintendo Switch Online smartphone app. (Persistent internet and compatible smartphone or tablet required to use the Nintendo Switch Online app; data charges may apply.)
Matches with players in the same geographic region will also take higher priority.
Side note: Nintendo Switch Online membership (sold separately) and Nintendo Account required for online play.
Global Smash Power
See how your skills stack up against other players around the world. There’s even a special mode just for the top players called Elite Smash Mode. Just think of the bragging rights!
Preferred rules
Set the rules for how you want to play and matches with those who prefer similar rules will be prioritized. Or, you can always just let your opponent choose.
Two-player
Join a friend and play online using a single Nintendo Switch console. You can team up together or battle separately against your opponents.
Spectator mode
Watch other players battle it out in spectator mode. It’s a great way to pick up gameplay tips!
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Source: smashbros.com
Pokémon Blog 
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