which champions are good tank shredders

Vayne says hi. But Vayne's overrated in general.

A good Fiora player? (Which is quite rare) Jinx with near/full build? Or any ADC really at that point in the game?

Actually most DPS champions, which includes most ADCs.

Every ad champion, because armor pen is op this season.

Kog is a good tank shredder, but he's horrifically under-tuned at the moment.

Shyvana

id say twitch, not really a tank shredder but an entire team shredder.

any ADC with

followed by almost every other adc, but stands out in the "tank shredder" category

followed by (only if you're good) (but tanks usually have a lot of cc, which really counters Yi. If you meant juggernauts, then nvm) (but he's not that great atm) / (sub-par but still efficient due to hybrid dmg) (has potential but positioning is crucial) (similar to Kayle/Jax except she has %hp dmg as well, but definitely less efficient, especially after her nerfs awhile ago) (just due to his itemization and dueling potential together synergize to fck tanks up)

is surprisingly good at shredding tanks, granted it means you need to ult the tank but if the tank is a bigger threat than the squishies it's fine. For reference, between your ult, duskblade, standard armour pen in your build and passive, you can easily one-shot or take a vast majority of a tank's health bar. One of the few things I like about him tbh.

Vayne.

As long as you aren't a pussy and as long as you ignore every person on your team who requests that you go tanky.

Kayns red form i'd say