If you want content for Dawn, you do have to shop at other storefronts.

OTOH, if you purchase Lyrra's Fit room magnets for Dawn & Dusk (sold right here at 'rosity), it is a 30 second process to convert an outfit.

I have dozens of V4 outfits that have never been worn by V4, but by Dawn, Pauline, Roxie, Miki, Sydney, Mariko, Jessi, et al.

The biggest problem is that with most vendors, all of their characters look alike.