Omg! Thank you! This explains why I couldn't figure it out. Very helpful!
edit: Oh, turns out this is STILL not what I am looking for BCAT is for real switches not emulators like RyuJinx, I believe. I am trying to find a way to get wondercard items into RyuJinx Scarlet. I'll just have to give myself the items I guess. I was hoping to be more legit than just giving myself things. But alas. Thanks anyway.