I did it in one of my secondary bathrooms, but still in process so the final outcome isn't known yet! I did narrow medicine cabinets that are 20" wide and the sconces are linear 3" wide x 26" high. The vanity is 78". I also only did one sconce in the middle.

Make sure you also add recessed light to the bathroom. All my bathrooms have 2 in the shower and at least 2 more in the bathroom, depending on size. Group the sconces, floor area and shower area separately and add dimmers to all.

Thanks @chispa! We'll have recessed lighting and hopefully good natural light! Do you mind sharing the sconces you chose? I'm having a hard time finding ones narrower than 5" that I like.

i used led mirrors (giant makeup mirrors) my setup is almost the same as yours

Thanks @M Riz. I like those too! But prefer the look of sconces if I can make them work.

@Abbey L, here is the sconce. You can choose different lengths, color temp (kelvin) and finish.

https://modernforms.com/product/mini-vogue/

"I've been looking at sconces anywhere from 5-8" wide."

How would these fit? 30" (vanity width) - 24" (mirror width) = 6" / 2 = 3". You only have 3" on either side of the mirror (and between the mirror and the wall). Go with over-the-mirror lights.

My bad @wdccruise! Sink vanities are 36" wide, not 30". That's what I get for late night attempted problem solving. So, given that, trying to figure out if smaller mirrors will still suffice and fit sconces or if it'll look too crammed on the 2 sides.

Here's a sconce I used in my master bath that may work in a tighter space. I have it paired with a more ornate antique mirror so I needed something very simple.

LED Wall Sconces - Energy Efficient Sconce Designs | Lamps Plus · More Info

Oooh, pretty! Thanks @Rachel.