"This is true. As the game is now, you cannot create friend lobbies online. You can only play online with randoms. You can still get friends together and play with local play, and you're free to play with four players on one Nintendo Switch system. You can also still challenge your friends to your creations and take on their designs through Course IDs and having them follow your Maker profile."
Nintendo

QUELLE und TEXT: https://mynintendonews.com/2019/05/28/nintendo-says-in-statement-you-cant-play-super-mario-maker-2-online-with-friends/

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