AYE! Cross-platform is indeed possible for they have announced that they want to separate the player base as little as possible.
I doubt that buying one copy would let you play on both supports at the same time. That would be ARRRRguably a treasure in itself for all of us but not so much for the editors.
I hope you find your answers on your journey with your little rascal and I will be sure to keep my only eye on the thread YARRRR!
