Queen Stephe is very similar to Steve in appearance, with the same skin tone, general shapes and features, but appears to be wearing blush. Otherwise, Queen Stephe is completely indistinguishable from Steve. She's the only member of the Royal Family to be a Minecraftian.
Appearance in "Castle Royale"
This is Queen Stephe's only appearance in SMG4's bloopers. Mario initially believed she was Steve in makeup when he saw her at first, but he later realized his mistake when he saw Steve and her in the same room. The Queen then realized herself too that she had been mistaken for someone else, and chased the red plumber in anger. Toad, who was in the same room, said that she was a "b*tch".
Her name is a pun on Steve's, constructed to trick the audience (and Mario) into thinking she's another of Steve's crazy alter-egos.
She is the only other Minecraft character (obviously excluding Steve and his various alternate identities) in the SM64 universe, and the only truly confirmed female Minecraft character.
While her husband and son are Mario clones, she herself is a Minecraftian.
She also appears to be partially mute, as Steve was in the oldest bloopers that feature him.