Azir's Ult + Flash
I don't think I've ever been able to properly Flash over Azir's wall, though the wiki says you should be able to.
Blinks are distinct from dashes and can bypass the wall (e.g. Flash, Arcane Shift and Crowstorm
Do you literally need to be right up next to it? I know Flash is a 425 range blink, but I'm not entirely sure on the width of the wall.