Yasuo vs Ekko

Hit twice with Steel Tempest (Q), on minions if needed, to charge the whirlwind. Cast it during Sweeping Blade (E): the strike becomes a circle.

Keep moving before taking a trade: Way of the Wanderer (passive) builds your shield while you move, and it triggers on the first hit you take.

Chain Sweeping Blade (E) on different targets to reposition or dodge: each target has its own cooldown, so the spell comes back almost instantly.

Save Wind Wall (W) for a projectile that decides the teamfight, like Jinx's ult, rather than for poke: it blocks for 4 seconds, on a 25 to 17 second cooldown.

Watch for your allies' knock-ups: Last Breath (R) can be cast on any airborne champion, whether the knock-up comes from your whirlwind or Malphite's ult.

Take short trades: his third hit on you, auto or spell, triggers Z-Drive Resonance (passive), with bonus damage and a burst of speed.

When Timewinder (Q) expands on you, leave the field: it slows you, and the device hits you again on its way back to him.

Leave the Parallel Convergence (W) sphere as soon as it appears: if he steps into it, it stuns every enemy inside.

When he's low, don't chase him blindly: Chronobreak (R) brings him back to where he was 4 seconds earlier and damages nearby enemies. Ready your spells on that spot.