Everyone says Yasuo is op which is true but he definitely requires skill. His ult is skill shot based because you have to hit his whirlwind which is extremely difficult to land (Coming from a Yasuo main). So Yasuo is only op is you have considerable amounts of skill and potential. Right?
Who requires more skill Brand or Yasuo?
He takes no skill. His Q is an aoe linear attack that is easy to land, His tornado is easy to hit considering the animation is hard to see where it is going. His W may be a long cooldown, but it blocks all projectiles. ALL OF THEM. He doesn't use mana so it has no punishment to using it, he E is practically infinite to get to a champion through their minions, and you cannot miss your ult. His R cannot be missed.
I am not saying a player with no experience can easily play him, but you don't need to be a pro to be able to play this braindead champion. "High skill cap" It's dumb to have a champion that is viewed as OP by 50% of league players and Skillful by the other 50%. This "High Skill Cap" people claims he has is really non existent.
"So if Yasuo doesn't take skill, then every assassin doesn't take skill" Not true. He specifically takes no skill because, yes a lot of assasins one shot the enemy, but no, not all of them can easily disengage or get out. That's the role of an assassin. get in and get out, but some assassins get deleted before they can get out. Yasuo's windwall is not that hard to place and blocks all projectiles. This alone is easy enough to get away with, his airborne is easy to hit, buying him some time to disengage.
He does incredible damage at level one and during laning phase. He can pretty much 1v1 anyone at level one with his Q, and ignite. He can easily tower dive anyone.
His passive gives him a shield that can save him from a lot of abilities. His crit is through the roof.
He might not be able to spam his W, but he has no punishment to using it. Look at Ahri, if she throws out three spells, shes completely out of mana. They may be at a short cooldown but whats the point if she cant use them anyway. 
In Conclusion: His Q does incredible damage and is not at all difficult to land. His W blocks all projectiles and allows him to zone out players with projectile based abilities. He has no punishment of using it. His E is infinite as long as it is not on the same target, which most of the time it isn't. His R is unimmisable. You cannot miss this ability. His Passive gives him a shield that absorbs practically any abilities thrown at you, which defeats the purpose of most Mid-Laners' combos.
So no. this champion does not take skill.
He's too hard to do well with right now, so yes
Not dying early on requires skill. Sometimes he can bully lane, other times range can destroy him.
The biggest complaint is the Shiv+IE steamroll that he does. (This was nerfed recently by moving IEs crit to PD which doesn't help Yasuo as much.)
Once Yasuo has maxed CDR on his Q through attack speed, his IE/Shiv hits on his attacks make him kill squishies nearly instantly. A fed Yasuo can terrify the rift mid game with brainless engages spamming his Q. Late game he tends to get put in check if you can root him and blow him up.
There is always skill in every champion, Wind walls can change the game as well as well timed ults/knock ups.
Despite what people will say 
does take skill and will take time to learn and master he has a decently high skill cap. He's not like an 
where you can just pick up and do random shit and actually do good.
And tbh he isn't that OP, 
are stronger mids than him right now imo
I tried Brand and Yasuo, Yasuo is so easy in comparison, with brand you have to do the combo just right, and with yasuo you need to land ONE skillshot and press R. His q can't even be intercepted, unlike brand's q, he has a shield for taking poke, and has a gap closer. however Yasuo isnt OP, he is just easy, so even low level players can use him. What I hate is people saying yas takes skill, he is more faceroll than Fizz, also during laning he never has to go back because he is "oom" he can stay till he gets lots of gold, and he can build glasscannon, tank, and slightly tanky, but Zed is still a better midlane AD assassin
Once you said i'm a yasuo main i stopped taking your word seriously and brands whole kit is skill shots and yasuo isn't so yes brand does take more skill and also brand can't escape as easily as yasuo can 
I would not say that landing his Q or R take all that much skill. It has a pretty wide hitbox and travels relatively quickly. It's neither easy nor hard really. Yasuo can activate his ult any time he is in range of an aireborne foe. So any allied ability that knocks up enemies can be used for Yasuo's ult. This removes the requirement to hit your Q whirlwind.
What it takes is timing and understanding the battlefield. Ult-ing anytime you get the prompt will, more often than not, drop you into a potentially lethal situation.
This can be a good thing if you are SKILLED with using Yasuo's Sweeping Blade which damages and repositions. This, I think, is key. Skill with Yasuo is determined by your ability to choose targets for Sweeping Blade to put you where you want to be and maintain a way out of bad situations.
That's my two cents.
Yes, he requires skill. But not with Steel Tempest or Last Breath. Sweeping Blade is what makes a good Yasuo.
I'd say Yasuo, but only because I find more feeders on Yasuo than Brand.
