just as the tittle says "SWORD" (singular) & "SHIELDS" (plural).
It has a good reason to be like that, if you have more than one weapon giving you ATK then you will end one-shoting every enemy and making it boring.
On the full version all equipment items will have their own passive effects, weapon for offensive, and shields for defense and to trigger different effects for different builds.
I'm glad that you had fun playing my little game! :)