Ulquiorra is an Arrancar in Sōsuke Aizen's army. He is also the 4th Espada. You can see the leftovers from a hollow mask on the top left side of his head.
Ulquiorra isn't the type to play around. so he would probably kill Shunsui before Shunshui gets the chance to try anything, but if Ulquiorra played around, yeah, Shunsui's tricks can give him the win.
Tbf tho, Ulquiorra seemed to not want to mess with Aizen either way. I think it can be argued Aizen>>Segunda Etapa Ulquiorra, I wanted to know a general opinion more than anything.
Ulquiorra takes this he's the only espada with a second form and as awesome as Starrk is he got owned by Shunsui in Shikai while Ulquiorra got owned by Hollow Ichigo.
I think ulquiorra takes this simply because his agility is much greater than yammy who simply had to tank attacks. Ulquiorra is a harder target to hit and packs some firepower as well. R1.
Any less effort on Gin's part will give Ulquiorra time to adapt his reflexes to KnY's speed like Ichigo did, after which Ulquiorra will take GIn out with Cero Oscuras.
Battle between Yammy and Ichigo takes a different turn - Ulquiorra and Yammy decide to fight Urahara and Yoruichi instead of running away, and a fu
Ulquiorra having a second release or getting thrashed by VL at 50% really doesn't prove anything about his superiority to any of the Espada above him tbh... Yammy got this