In the game, shields are used to attack and block. Yet, there is no listing for which weapon type a shield is classified as. There seems to be no attribute that affects shield attacks.
Suggestion: Classify shields as “stamina” weapons (as blocking is stamina-related). It would also allow them to be paired with either longsword, mace, axe (strength) or short sword (agility) weapons without an undue advantage to one or the other.