I have a question, there are two ways (that I know of) of shaking the arba minim on Sukkot (east,south,west,north,up,down) and (south,north,east,up,down,west). My question is if those different ways would be called different nussachim or different minhagim?
Definitely a minhag. A “nussach” is a version of something, therefore including davening, learning, singing etc. Your “nussach” is also a minhag – i.e. “My minhag is to daven Nussach Ari”.
“minhag” can refer to the format of following a Halacha, as here, and there are more than two ways. In rishonim there is mention of ma’aleh u’morid, molich u’mavee. There is also chiluk with associated waving or shakes to the x/y axes moves, is it one move or three moves, one move and three shakes, or the combination? I have heard of a concept of being yotze all deos. Not a nussach issue by any means. Hag sameach y’all