What about will.i.am's outfit?
Remind you of any Winx character? If not, I'll show you.
Anagan. The long coat, the big collar and tight pants screams Anagan. Even will.i.am's shoes kinda look similar. The only difference is the colour.
Last of all, Britney's hairdo remind me of Daphne's.
So was the video Winx-inspired? I'd like to think so, but it's unlikely.