Source Gaming has identified a small note on the Japanese version of the Super Smash Bros. for Wii U/Nintendo 3DS Fighter Ballot that was held a couple of years ago.
During the Fighter Ballot, players could vote for the game character they wanted to see the most in the game. The small note in the Japanese Fighter Ballot says “information received from this vote will be used for consideration for this software’s fighting characters and for reference for future software”.
Pretty much means the entire roster of characters from the previous games are being considered for Super Smash Bros. for Nintendo Switch!
— Source Gaming (@AllSourceGaming) April 3, 2018