Use a hidden item. Takes time, but no item are expended.In-Game "Help" Description.
Stash (とっておき, Totteoki?, lit. Prized Possession) is a skillset used by the Alchemist dressphere in Final Fantasy X-2 that allows the user to use items without actually expending them from the inventory. Stash has a longer charge time than the Item command, but once a Stash ability has been learned, the party member can use items through it in an infinite supply.
List of abilities
|Potion||10||Use a spare Potion that you tucked away.||None|
|Hi-Potion||40||Use a spare Hi-Potion that you tucked away.||Potion|
|Mega-Potion||120||Use a spare Mega Potion that you tucked away.||Hi-Potion|
|X-Potion||160||Use a spare X-Potion that you tucked away.||Mega-Potion|
|Remedy||20||Use a spare Remedy that you tucked away.||None|
|Dispel Tonic||20||Use a spare Dispel Tonic that you tucked away.||Remedy|
|Phoenix Down||30||Use a spare Phoenix Down that you tucked away.||None|
|Mega Phoenix||200||'Use a spare Mega Phoenix that you tucked away.||Phoenix Down|
|Ether||400||Use a spare Ether that you tucked away.||Dispel Tonic|
|Elixir||999||Use a spare Elixir that you tucked away.||Ether|