Inland Revenue weighs in on crypto (page 3)
Summary: If you get paid in crypto, you still need to pay PAYE on your wages as though you were getting paid in NZD, at a rate determined by a valid exchange (one which operates in accordance with laws such as know your customer) - a NZ based exchange will do just fine.
The parallel they draw is that crypto is like property, so FBT applies. Stable coins can be treated as money, pay your tax G.
I expect that the usual trading vs investing definitions come into play around gains made in crypto and whether they are taxable. (Intent when purchasing, and frequency of buying/selling, etc)