Riven Against Yasuo,who counters who?

More people say to Riven counters Yasuo,but Yasuo has the W for block the Riven's R,and his E can easy escape. Sure,Riven can W and go attack him,but Yasuo doesn't run (Exception when him can E on a minion in his back.) , Riven can use smart her ult.But at level 6,it's to hard to win somebody. SO: Question: Does Riven counter Yasuo ? OR: Can Yasuo counters Riven?
vs