[RMVX ACE] STORE ITEMS IN A SEPARATE PILE

Hi! I want to make a feature for my game similar to Undertale`s Dimensional boxes, but without restrictions on amount of items.

Imagine the main hero has a backpack full of useful and useless items. He decides to store some items in a separate pile and leave only the most important items in his backpack. He can come back to this pile and pick some items from it or put new items.
How is it possible to implement?

author=Marrend
It might be possible to do with Show Choice, Conditional Branches, and variables, but, I imagine it would be exceptionally tedious.

Maybe look into this script?

Thank you so-so much!