Asriel on 08 March 2018
http://www.eurogamer.net/articles/2018-03-08-mario-tennis-aces-launches-for-nintendo-switch-in-june
A Japanese retailer has leaked Mario Tennis Aces release date: June 22nd. Online and local multiplayer and motion controls confirmed, too, it seems. Amazon also had that date down for Europe - as well as August 17th for Octopath Traveller, so it looks like that could be true, too.
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