After the Splatoon 3 Direct last week, Nintendo confirmed that Splatoon 2 save data can be transferred to the sequel. This can be done once per Nintendo account and save data from the second game must be on the same console along with the same user account.
Doing so provides some pretty good bonuses like three Gold Sheldon Licenses which can be exchanged for Main weapons irrespective of the player’s level. Anarchy Battles, the game’s de facto Ranked mode, are also unlocked from the beginning and based on one’s rank in the second game, they can start with a higher rank. You’ll also match against players with similar skill levels from Splatoon 2.
Nintendo also clarified a few things regarding save data. Story Mode progress can be stored via the cloud if you have a Nintendo Switch Online subscription. However, online data like player level, rank, items and gear are stored on the server automatically and connected to one’s Nintendo Account. So as long as your user account is tied to the Nintendo Account, it’s possible to play multiplayer on multiple different systems.
Splatoon 3 is out on September 9th for Nintendo Switch. A demo goes live on August 18th, allowing one to participate in a pre-release Splatfest on August 27th.