I rarely ever get any other boots since greaves is amazing on Yasuo. The only time I ever get plated steelcaps is if the enemy team are full AD. I usually don't swap boots late game since Yasuo needs the attack speed for his Q, and games rarely ever get to that point.

Since the immortal buffs I almost always go with this item. So, unless the enemy team are super tanky I would say immortal shieldbow is the default mythic for Yasuo.

Thanks fam <3