You can scroll-up/scroll-down with your mouse to change the number of berries 1 by 1. Also, you can add more berries than the same quantity of Mons cards that you have, just in case for those mons that use 2 berries or 2 diff berries
Ah, I want to say I tried that and it didn't do it. Gonna make sure to look into that. Did seem like a weird thing to not add given all the other wonderful Quality of Life things integrated.