A common Yasuo build in a game where he isn't stomping but isn't doing bad is usually Two crit items > Lifesteal > Two defensive/ defensive-offensive hybrid items.
If you want more damage instead of the dueling/chasing power of PD. Yasuo doesn't really need the waveclear from Shiv, so PD usually wins out
Still absolute cancer on him. Take if you're top/ or behind in mid for the extra health
This is an extremely common buy, but with the changes coming in soon, we don't know. Most say that he will enjoy it even more.
Honestly, Yasuo can build pretty much anything that isn't an AP item and do relatively well with it. Some of the complainers also note this: the absolute flexibility of his item pool. Of course, some items are better than others, and other buys would be completely questionable, but you usually want to start off with your crit items and then build into your defensive choices however the game looks so you won't be blown up by any semi-competent team the moment you dive them. They have AP damage and annoying CC?
.
for teams with sustain out of their ass.
to get places faster. They have a Tryn, Jhin, Cait or a fed ADC?
Really anything works, you just have to observe what's the situation of both teams and build accordingly, as with any other champion. The only difference is, of course, Yasuo's item pool pretty much covers everything that isn't AP or Thornmail.