Cosmic vs. Dark Star

I've noticed that each of the Cosmic skins have a Dark Star march-up in their role, and vice versa.

Jungle: Cosmic Blade Yi vs. Dark Star Kha'Zix Mid: Cosmic Reaver Kassadin vs. Dark Star Orianna Bot: Cosmic Dusk Xayah & Cosmic Dawn Rakan vs. Dark Star Varus & Dark Star Thresh

My question to you is: who would you want the top lane match-up to be? You don't have to put both; you can just put what top laner you'd like to see get a Cosmic/Dark Star skin.