Monster Hunter Generations Ultimate allows cross-play between 2 platforms

Supported crossplay platforms
Release Date: Aug 25, 2017
Official Website: Link
Summary:
An enhanced version of Monster Hunter Generations. It features new monsters, hunting styles, and the more challenging G-Rank quests. Game data from Monster Hunter Generations can be carried over, with a one way transfer, to Monster Hunter Generations Ultimate. Game data can also be moved between the 3DS and the Switch version of the game.
Supported crossplay platforms:
Monster Hunter Generations Ultimate is supporting cross-play across multiple platforms. Currently it is possible to play together with your friends on Nintendo Switch and Nintendo 3DS.
Monster Hunter Generations Ultimate is also known as:
  • MHXX
  • モンスターハンターダブルクロス
  • Monster Hunter Double Cross
Supported game modes:
  • Single player
  • Multiplayer
  • Co-operative
Supported player perspectives:
  • Third person