Can I use a GC Loader to run LoZ: TWW on original hardware or does that still count as an emulation?

You can use neogamma, you cannot use nintendont, as nintendont has faster load times. You must use a disc of the game, as WW was never released digitally. If you use anything other than neogamma, it would count as emulation, which is allowed up to a certain cutoff for each category.