I'm sure there's other alternatives, but what works for me is:How do you actually hurt shield enemies like the zombies?
You either attack before they begin blocking with their shield; it's easier to achieve this as they're moving into the square in front of you or from one square away with a reach weapon (spear, halberd, restraining pole, etc). Or you rely on stamina damage, instead of hp damage, using restraining pole or shield bash - possibly others?
Sex damage is probably viable as well, assuming you have succubus?