If you’re taking NZQA Scholarship and you think that you’ll perform well in these. Then there is not as much need to do the Advanced Placement tests. However, if you think that subjects within your skill set have not yet been covered, and you can do this through AP’s, then I’d definitely recommend it.
Time is also an important factor, I’m not sure what year you are in, but if you have the time to do the AP’s - then do it. The more high-level results you have, the better. It demonstrates that you can manage multiple curriculums, whilst still performing well, at the same time.
You should also be considering SAT II (Subject Tests). This would be to fully demonstrate your intellectual flexibility and to leverage the existing knowledge.