Welcome to AFF, Sunday horse. A port in a COVID storm! Lets see if eny experts disagree with me, but here goes...
*who do I contact (virgin or Eithad) to cancel/change? Do I have a choice of cancel/change?
As it's Etidad points, I'd try them first and find out what they say. Emphasise you have been effectively locked out by NZ Govt - force majeure.
There are as many policies as there are airlines.
*will this incur fees/costs?
See what they say. There are so many cancellations on so many airlines and so mny different policies soit's impossible to keep up.
*have some non refundable accommodation? What (if any ) is Our rights with this (have been reading heaps of sites and someone did mention something about consumer rights?..now can’t find it .) Grovel, Refund, rebook or bad luck?
Check with the booking provider. many are offering cancellations As above, you've been effectively locked out of NZ
*some of this accommodation has been booked direct and some via Agoda/hotel.com. Do I contact direct or via travel site?
Whoever you booked with
Cheers skip