I made cards for our family game and originally thought I'd make equipment cards as well, but eventually I ended up taking a completely upside-down approach, and made cards based on action types.
So we have red cards for anything that takes a regular action, blue cards for bonus actions, yellow cards for reactions, green cards for anything that takes long enough so that it's not doable in combat but can be done within a short rest, brown cards for special stuff that takes longer than a short rest, and grey cards for modifiers that take no action at all.
I design and print cards on a need basis, meaning that I don't try to have all cards for every class ready beforehand: I see what my players choose at next level, and make only the cards they need.
These include spells, (sub)class features, racial features and feats. They could also include equipment and magic items but for a couple of reasons I am not doing those yet for the time being. The main reason being, the whole purpose of our cards is to remember what your PC can do in combat within the action economy (like, what else can I do with my action, do I have time to do something else with my bonus action etc.), and also to have the full text on the card instead of having to flip through rulebooks while playing. At the very beginning, I thought I'd have cards for each basic weapon, but since they don't really have much rules to remember besides attack bonuses, they just get written on the character sheet. Magic weapons could be written to cards, but typically I like them to be mysterious, with properties to discover or develop over time, and making a card that tells everything doesn't suit that approach to magic item for me.
