I went through my stash and this has a few close shades. I've seen the Lapis of Luxury comparison on MUA showing they were different enough (which is why I bought this). In my stash the closest polish I have is China Glaze Secret Periwinkle. Next up is Revlon Modern Grace and Bettina Flip Flop.
|Boxer Shorts, Secret Periwinkle, Boxer Shorts, Secret Periwinkle|
|Pointer & Ring = Essie Boxer Shorts. Middle & Pinky = China Glaze Secret Periwinkle|
Essie Boxer Shorts and China Glaze Secret Periwinkle are super close. One just leans more blue and the other more purple. They are about the same brightness and both are opaque with two coats.
Here's another comparison pic with the other polishes that were somewhat close:
|Top left - Essie Boxer Shorts|
Bottom left - China Glaze Secret Periwinkle
Top right - Revlon Modern Grace
Bottom right - Bettina Flip Flop
I hope that makes everyone's shopping decision a little bit easier. If you already have Secret Periwinkle in your stash, I'm not entirely sure you need both. It's personal preference in regards to whether you want your polish a bit more blue or a bit more purple.
I hope everyone has a good weekend! :)