>>1018612
I figured it out in the end. got zbrush on the high seas and extracted the matcaps as tiff files, then saved as png and autistically made sure that they matched how they look in zbrush by comparing the raw tiff, the saved png, the tiff opened in blender and the preview of the matcap in zbrush. the only one it didn't work with is Blinn
not sure if it's wise to sculpt with these darker ones though, likely not
first pic is the default blender grey