Nintendo is pretty happy with their partnership with Microsoft in regards to cross-play (based on a recent ad celebrating it and some words of wisdom from NOA president Reggie Fils-Aime), especially since Minecraft just plain old fits on a Nintendo system. They're also working with several other platform holders in regards to Fornite, and Nintendo president Tatsumi Kimishima had a few encouraging words to say about that whole process in a recent shareholders meeting.
There is one caveat though: Kimishima clarifies that Nintendo games won't be making their way to other platforms anytime soon: "I will have to refrain from commenting directly about (crossplay in) Fortnite and Minecraft because those are not Nintendo titles. But I will say that our fundamental way of thinking about offering Nintendo titles on other platforms remains unchanged."
Susumu Tanaka, senior executive officer also chimes in with a thinly veiled response that implicates Sony: "Crossplay basically comes about from conversations between publishers and platform holders. We are inclined to do what we can to help publishers incorporate crossplay when that is what they want. The other parties involved also have a say in whether we are able to reach this outcome or not, so we will continue to discuss it with them."
"Them" is clearly Sony in this case (who refuse to cooperate with Microsoft and Nintendo in regards to cross-play), and the "continue to discuss" part is important. Nintendo seemingly isn't giving up on cross-play partnerships with the company, both of which run out of Japan.