Hey GregFTW,
there’s no “out of the box” functionality for something like wearable things but it should be very easy to add an inventory to your “wearable” items and then access it! Just ‘copy’ the BP in GenericContainer! What you might have to do is configure your widgets so that the inventories the user wears are displayed as you want them to!
For an item to have it’s own custom ‘use’ function, that’s almost ready too. Just open your BP and override the “use” function already implemented in GenericItem! Should be extremely easy!