Vicarious Visions Artist, Kara Zisa who was responsible for creating the save/load screens for the Crash Bandicoot N. Sane Trilogy has uploaded footage of the game to her portfolio, but the interesting thing is the fact that the the entire footage contains Xbox controls.
https://www.youtube.com/watch?v=_MVOYYFQtM8
It's not entirely shocking and this isn't concrete information that the game will come to Xbox, but it definitely gives us another reason to believe that it probably will come to Xbox. It's harder to guess when the game will make its way across as it's clear that the game is selling PlayStation units. It's not unreasonable to expect that we won't see it on other platforms until next year.
It's been very unclear since the game was first announced over a year ago (and increasingly more confusing) about whether theCrash Bandicoot N. Sane Trilogy would be exclusive to PS4. It was initially thought to be the case after PlayStation Ireland Tweeted out that the game was exclusive, but then they deleted the Tweet just a day after putting it live putting more petrol on the fire.
Here in Australia, EB Games was marketing it as a PlayStation 4 exclusive for months, before changing their marketing and removing the 'Only on PlayStation' tagline from the marketing.