Any sprites that end up in the "Unreferenced Sprites" folder are likely unused. 

Also note that sometimes, some sprites might end up cropped and not like they were in the original sprite sheet, this is due to the only data that can be pulled for splitting sprite being from the animation file, so they end up cropped like the are in the animation. This can be mainly ignored for normal character sprites, but will more likely happen with Special Skills and UI elements.

Most of the split sprites are only in the Global (English) folder due to each animation sharing the same sprites minus the text.