why does darius' E stun for 1 second after he pulls?

it doesn't stun

it's a 0.5 sec knock back that puts you nearly 200 units in front of darius

this was made so he can't immediatly walk behind you when he hooks you like he used to before the rework, and prevented any possible disengage as for example jayce wasn't able to knock him back in the good direction

Didn't notice it but it should slow for 1s at ~90% or so if I remember well.

same reason ahri isnt nerfed. lul

it doesnt?