You really don't play Annie much do you?
She's not that simple, nor is she that complex.
Annie doesn't "Duel" but she does trade which is basically the same thing unless you want to nitpick.
Her High AA Range makes trading as her very easy, hell AA bullying is literally a tactic that was made popular BECAUSE of Annie in the earlier seasons.
She has amongst the highest AA range in the game, being amongst the top 5 - 10 highest in the game when champions aren't using AA Modifiers.
If you seriously think AA Range doesn't matter, it makes me wonder why people hate Caitlyn so much.
In lane charging your stun on minions is 100% recommended.
The only time you SHOULD be using your E to charge your stun is during trades, otherwise it's not really necessary to waste what is her only Defensive spell.
You can charge your stun for free off of Lane minions.
The idea of her E being a filler spell is an idea that died in the Mage update.
Her Damage reduction is pure gold in regards to surviving longer in lane.
I never said you should max AOE on Annie, in fact that's probably the worst thing you could do.
Just because your W isn't a projectile doesn't mean you HAVE to max it first.
Her Q is still useful, but if it comes down to it your W is a nice fall back if he windwalls your Q stun.
Even at level 1 Annie's Q is on a 4 second CD, whereas Yasuo's is Windwall is at a minimum 26 second CD.
Given Annie can get into range, she can get off about 3 - 5 Q's in the time his Windwall is down.
If you SERIOUSLY think Annie ever has Mana problems it's very clear your never play this champion.
Her Q is refunded when you kills minion, so that's literally free farm.
Even when you don't get it refunded the mana cost is low, and her Mana regen is quite high naturally.
If necessary you can take some points into the meditation mastery to counter-act it if you're not confident.
Your W should only be used when trading, and the mana cost doesn't ramp up till you begin maxing it anyways.
Your E is only a measly 20 mana no matter it's rank.
Tibbers cost 100 mana, but by level 6 you will have a mana item anyways.
Before first back it's often just better to farm 900 - 1200 gold so you can get
or
But even before that it's not entirely necessary to have these items to keep up with Yasuo, just AA bullying him and procing thunderlords with AA - Q - AA is enough to keep up with him early game.
I can confidentially say Annie is a much better choice into Yasuo then Kennen is.
Her stun is easier to access, she's better for setting up ganks, her burst is almost unmatched, She effectively never falls off and her laning phase is extremely strong. Her stun is longer as well as not being set-up reliant.
Kennen being able to stun Kennen in less then 4 seconds isn't really anything special when Annie is able to do it almost INSTANTLY with a W or Tibbers.
Lastly it's funny when you talk about Annie not being able to Zone Yasuo when in fact her Stun is better at zoning then his Whirlwind, as it's permanent, as opposed to his being 10 seconds.
Once he uses his Whirlwind or runs it down, Annie can use her stun without a care.