monks-shops VS foundryvtt-magic-items

monks-shops - This module is to provide some pregenerated shops for DnD5e that work with Monks Enhanced Journals. As well as adding some roll tables for common items. So you can create your own shop quickly.

FoundryVTT Magic Items - This module for Foundry VTT and specific for the DnD5e system, adds the ability to create magical items with spells or feats that belong to the item itself, such as staffs or magic wands, which will be automatically inherited from the character who owns the item.

Magic Items - Allows adding additional spells and such onto magic items directly. Very useful for items that function on charge systems that can be upcast, though a little tricky to work with.

Well there's your problem right there.

Magic Items might help you. I believe you can set it to use multiple charges and scale with number of charges.

a solution could be to code your cutom "feature" into custom magic spells and use the mod "magic items" which let you add spells to magic items with customizable charge cost per spell, number of charges, charges regained at x and so on

What you want is the Magic Items Module... it works with MIDI-QOL and DAE. https://gitlab.com/riccisi/foundryvtt-magic-items

Magic Items

There's an issue for this raised on the module's gitlab page: https://gitlab.com/riccisi/foundryvtt-magic-items/-/issues/82