It wouldn't be temporary items since I imagine that would be too much work for the Dev team. It would simply be more slots dedicated to specific types of items. The difference between this idea and simply adding more types of inventory like Mog Satchel is that you can use the item from these partitioned inventories. They could even rewire the program such that using items from the battle menu shows brings up your "Consumable" inventory only. And when you're equipping gear, it could just bring up gear from the Equipment inventory only. These changes should also help GMs by reducing the number of instances in which a person accidentally drops equipment because they meant to drop equipment they no longer need.