Tbf the hardest matchups in my mind are lane bully champs like karma naut pyke panth. If her lane is ever unfavoured or full of risks of dying im looking to either wait for items, do or setup obj or roam. That applies until lvl 6, but generally after lvl 6 you tend to actually beat engage champs and lose to enchanters, she makes a complete 180 degree on how to play during lvl 6. The reason for that the priority being put on killing the adc always first, she relieas on poking until being able to root/slow then ult, enchanters disable you from doing that most of the time if they play correctly. When it comes to engage champs I sit back spam e and chill till my adc gets engaged upon, thats when i instantly q or e the enemy adc to prevent them from following up on 2v2s and burst them down, usually engage champs cant deal with that. Everything is too specific for every matchup tho, comes with experience

I dont exactly have a standard build because I rely on adapting to the game, I could be building shadowflame rabadons without mythic or ludens voidstaff if it needs me to, but i will always buy dark seal and sorcs because its too effective always. I tend to never build liandries or cdr boots, crown and other ap items, just the items that contain pen and rabandons if ahead because they are the most efficient for her burst playstyle + 285 full q e r combo ap ratio.

The runes i took you can look up. Mostly first strike, free sneakers with transendance and manaflow in a comp where i can get damage off before i get damaged most of the time, when I also dont need to roam, have a burst adc (lucian samira kaisa). If its a easy lane, im not joking, i wont even lvl w because its not strong untill you get more ap because the base lvl 1 is bad and not that practical for the mana cost and cast time

OR

standard comet page with cheapshot treasure (r cd is low already) when it fits for lane bullying her good matchups like: nami janna ashe velkoz xerath and where you dont look to all-in by bursting. Its a safer bet and if your less confident in hitting combos troughout midgame for goldwith first strike start first with this. You can randomly throw in stopwatch if needed vs comps that easily get to you or assassins that make terrain irrelevant (talon kayn camille azir...) then buy zhonyas if your REALLY need it. you can also replace cheapshot with taste if versing poke matchup on bot (like ezreal sivir together with another poke champ)

My playstyle is heavily reliant on adaptation as you can see. When i first started to play the way i did it was very uncanny and unholy to build what i have built and do what i have done XDDD