Other fan favorites like Kim Kaphwan are also likely to return given that he's one of the most popular in the FGC, along with Ralph and Clark.
One of the game's most popular characters, Athena, hasn't been shown but it's likely she'll return. And given that Kyo is in the game, he may have his classic KoF Team that features Benimaru and Goro Daimon, or the wannabe Shingo Yabuki (who had managed to unlock some small sparkly powers in his last outing, along with Kensou unlocking his Dragon powers).
So don't be surprised to see Terry and Joe join Andy as Team Fatal Fury. Given the characters that they've revealed so far and the fact that each character is part of a team, it stands to reason that we can expect many of the classic teammates to return as well. And speaking of fighters, some of the 50 characters were revealed in the trailer those who will be present in this upcoming title will include favorites such as Kyo Kusanagi (the main protagonist for most of the earlier King of Fighters games through the mid 1990s), Iori Yagami (Kyo's arch nemesis), Angel, Kula Diamond, King (one of my own personal favorites from Art of Fighting), Billy (from Fatal Fury), Leona (a King of Fighters native), Chang Koehan (which likely means Choi will be in the game, too) and Andy Bogard (the brother of Fatal Fury's former main protagonist Terry Bogard).