At Smashcon it was confirmed by Dan Fornace, the creator of Rivals of Aether that the game would eventually be making its way to the Nintendo Switch. Fornace confirmed that the game would be arriving on the Nintendo Switch one day with the main issue is having to redo the entire net code due.
“One of the biggest upgrades is that Rivals will be going from a two-player online game to up to four players, which means you’ll be able to queue for 1v1, 2v2, or free-for-all online. We’re also updating the friendly lobbies system, allowing you also to go up to four players, but you can go past that and have spectators. This allows you to do rotation lobbies. You can also spectate four-player matches. So these are all a ton of upgrades we’ve been working on behind-the-scenes.”
So it will be a ways off until you can fight your rivals on the Nintendo Switch.
Rivals of Aether is available on Xbox One and PC with a Nintendo Switch version planned for sometime in the future.
Source: Nintendo Everything