Her autoblock is immune to ability accuracy reduction. It's in her abilities.
How do you counter her then??
Nick fury works I have used him
Nick fury works I have used him Venom too.
How to counter Peni Parker- Hit into her block to get rid of her Sync Shield for 20 seconds, meaning she can't autoblock. Anything that lets you deal more damage into her block will help with this (attack modifiers, armor break, block penetration, etc)- Power Burn Immunity/significant resistance (eg Vision Aarkus for the latter)- Unblockable
Super Skrull with his undermine debuff. Makes his attacks unblockable whenever auto-block would trigger.