it broke on 1.50. but it was updated and it still works on 1.51. grab the update here:
https://gbatemp.net/threads/animal-crossing-new-horizons-cheat-database.563423/page-43#post-9221740
https://gbatemp.net/threads/animal-crossing-new-horizons-cheat-database.563423/page-43#post-9221740
It seems like this :
[Nook Shopping App to Empty Slot (Minus)]
Open the nooks shopping app or ATM, select the item you want, press - and it goes into your inventory.
Broke on v1.5.1, can someone confirm ? I have it configured the right way but pressing Minus doesn't add the item selected.