Saw this commercial for the Sims Korea with a popular Korean pop star (Hwasa), and the video shows fashion shows in the game with sims walking down a runway and striking a pose at the end. It talks ab...
I wouldn't swear to every single piece of clothing, but the vast majority of the outfits at least are things that are already in the game. I think sometimes they just use celebrities in these "Play with Life" commercials to highlight new ways of playing with existing content.