Yasuo's shield passive is the second highest base shield in the game
Yasuo's shield at max level shields up to 510 health, higher than any other base shield besides Shens ultimate.
When compared to
passive, who only shields 101 +14% bonus health with his passive at max level. Meaning Shen needs around 2922 bonus health (his full build usually lands him around 1950 bonus health only) for his passive to be able to compare with Yasuo. Not only is Yasuo's shield stronger than a TANK, but he also gets two passives, while Shen gets one.
When compared to support champions
they would need around 400-500 AP to match his shield. Considering they dont get much AP its safe to say Yasuo's shield is stronger
When compared to AP mages
they would need around 700 AP to match his passive, which by then would be a full build.
Its safe to say, Yasuo has one of the best shields in the game on his passive. While it is possible to poke it out unlike other shields, getting this for free on his passive on top of another already strong passive really says something.
's shield?
. That is 300 bonus AD already, meaning she has a shield equal to Yasuo's that is more spammable. This is increased to a 210 + 360 = 570 shield when she ults.