Crossplay

Is Splatoon 2: Octo Expansion crossplay?

Splatoon 2: Octo Expansion is only released on one platform, so there is nothing to cross-play with.

"This full-on single-player adventure spans 80 missions starring Agent 8, an Octoling who awakens on a dark subway platform. Navigate this mysterious underground test facility in a desperate battle to reach the surface of Inkopolis. Escape from these twisted depths, and you’ll finally be able to join multiplayer matches as an Octoling!" "The new adventure features 80 missions starring Agent 8, a new character who awakens without her memories on a dark subway platform. Navigate the twisted depths in a battle to reach the surface of Inkopolis. Once you escape, you'll be able to join multiplayer matches as an Octoling! - Play as an Octoling who's lost her memory in a new single-player adventure spanning 80 missions. - Navigate an underground facility to reach the surface of Inkopolis. - Take on a variety of mission types packed with new challenges you won't find in the main game. - Complete the campaign to unlock Octolings (Girl or Boy) as playable characters in multiplayer battles. - Unravel mysteries hidden below Inkopolis with Pearl, Marina, & Cap'n Cuttlefish."