Lars unleashed his inner Harlock and Stevonnie is rocking that stubble.

To the people who got extremely upset by the canonization that a male-female hybrid can have stubble, that says a lot more about you than the show.
As a design choice, it makes sense. But if you're like me then you simply feel, in this case, it doesn't make sense because Steven doesn't have stubble here, and are not 100% convinced Stevvonie is some sort of auto-puberty. Maybe Steven will grow stubble by the time they fuse, but if that were the case, then the promo art needs to be revisited to adjust his face accordingly. I figure this is something they would have to visit eventually, but the fact they went for it with a baby-faced Steven just doesn't quite match my idea about what Stevvonnie is.