They did some guidelines on that recently. https://en-americas-support.nintendo.com/app/answers/detail/a_id/63433 https://en-americas-support.nintendo.com/app/

They did some guidelines on that recently. https://en-americas-support.nintendo.com/app/answers/detail/a_id/63433 https://en-americas-support.nintendo.com/app/answers/detail/... But yeah, Nintendo is very concerned about diluting their brand and their trademarks, as well as keeping things family friendly.