Whether the one that already exists or otherwise, who knows. UPDATE: It's not just Brain Age.
Nintendo of America appears to be gauging interest in a "brain training" release on Switch.
A member of the Nintendo World Report staff received a survey from Nintendo that included the below question as its own page in the survey:
"At a price of $39.99, how interested are you in buying a brain training game that you can play with friends and family?"
A Brain Age title has launched on Switch in Europe/Australia (3 January 2020) and Japan (27 December 2019), but Nintendo of America has never spoken publicly about the game. A retail version was sold at a RRP of €39.99 with a Switch-capable stylus, but the download was priced at €26.99.
UPDATE 8:00pm ET: Some users are reporting receiving a similar survey, but with a WarioWare at $50.
