League of Legends (LoL) Question: Jayce's Mid Lane Match ups?

Jayce's best match up are assassins Mostly. I know this might not make much sense at first, but take Zed and Katarina into account - Jayce has a strong poke and a great disengage from both Hammer form and Cannon Form's "E" skill. If Katarina starts ulting you, you should be able fast enough to react with the hammer E skill - without losing too much health. Same goes to zed, if you E right after he ults, he can use his W to engage again, but a close target can easily be bursted down by the E Q combo.

The worst matchups might be Talon, Annie, and Syndra - either having invisibility so that Jayce cannot predict which way to set -up his acceleration gate smartly or solid CC with burst damage.

Just to note -->
However, Jayce is overall an exceptional mid-laner because, yes he can make plays and get kills during laning phase, but just safely farming and not dying will still make him one of the strongest mid-game poke and provide exceptional sieging power.

Well i played him today and Yasou was pretty hard for me. He can Block your harass with his Windwall and he´s very mobile so you can´t really hit him with your e+q or just q.
Also he has a lot of all in potential and will try to Poke you with his Knock-up q.
And when you are going into Cannon Mode he can easily e trough minions away.

I would say he is strong against close range (assasins generally) but weaker against longer range/poke like Annie, Xerath, Azir, Nidalee, or Lux. Akali can beat him after level 6 but he can pound on her pretty hard levels 3-5.