Isabelle is set to be released for Super Smash Bros. Ultimate in July 19th, 2019 for Japan and Europe, and July 26th, 2019 in North America.
Isabelle is the mayor's highly capable secretary from the Animal Crossing: New Leaf game. She can be forgetful sometimes, but you can always count on her for information about the town, and she's happy to cheer you on in all your mayor-ly duties. She also has a twin brother named Digby.