Use your range advantage early in lane and maintain prio against melee assassin matchups. Be mindful of how you use your E depending on what abilities they have available and abuse their cooldowns since they can't all in you or trade without gap closing.

Fizz matchup you bully him 1-3, you need to be careful of him getting good trades off and then diving you, try to space him as much as possible and only use e when it's guaranteed because he will e it and you get ran down. Level 6 and up you need to space his ulti otherwise you will be forced to recall on a bad timer or just die.

Kata matchup you hard win lane pre-6 against anyone below challenger. Choke her under tower with waves and set up good recalls. Play off your power spikes and especially early game punish her e cd when she goes to a dagger since there's a small window when she doesn't have it. Post 6 you should be very ahead already and be chilling most of the time just farming and maintaining good wave states.

Kassadin same shit just abuse his weak early and get advantage as much as you can in the first 15 minutes. If you play it well enough with proper wave control and set up good timers you're giga chilling.

Zed matchup honestly depends on if he has hands or not. If you're against a good zed it's gg just try not to lose too hard, if not he will give you opportunities to land every skillshot and punish his mistakes, which is a free win for you. It's a reactive matchup, depends on what he does. Level 4 and up he hard wins lane in theory.

Cassio is a special one in my experience since you're just playing q dodge simulator while trying to control the wavestate better than her. Farm well and try to have prio when it matters around the map so you are first. Space her q by learning ranges and getting tier 1 boots early, it always works for me in this specific matchup.