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As for the 3rd parties, they need to do two things:
Third parties have no obligation to make games for Nintendo gamers if they're isn't enough profit in it for them. They are fundamentally businesses. SE did good with Octopath Traveler. But western third parties don't make those kinds of games usually. AAA is dead IMO. They'll try again when sales continue to be good. Probably 2019 or 2020 at the very latest. Third party port teams like Panic Button get to work on the finished / almost done game usually. These games will be late until it is does in-house, concurrently with PS4/XB1/PC versions.
Currently (Re-)Playing: Starcraft 2: Legacy of the Void Multiplayer, The Legend of Zelda: A Link to the Past
Currently Watching: The Shield, Stein's;Gate, Narcos