*Sigh* This again. Vivian is a female in all versions, in the Japanese version she is called a man by her sisters as an insult. Goombella's tattle log refers to the man insult as well. Even in the end of the game of the Japanese version, Vivian is regarded as a female twice when the game talks about what each character did after the events of defeating the Shadow Queen. Vivian's catch card in the Japanese version of SPM also uses female to describe Vivian.
Must have: Legend of Zelda: Skyward Sword, Paper Mario, Donkey Kong Country Returns, and Kid Icarus: Uprising.
As someone stated before, it actually seemed more surprising to find out Hooktail was a girl. It's like they decided to make Hooktail a guy, and then change its gender at the last minute during the Gloomtail encounter.