Having an NZ specific frigate would be very expensive, we have never had a bespoke specific to NZ frigate design before
No one is talking about going to OMT and asking for a Frigate designed from scratch for NZ. OMT produced an evolved design for SEA 5000 based off the F370 Iver, to be OZ built and iirc was to include dual hangers, greater emphasis on ASW than the original F370 Iver and substantially cheaper than the F100 and Type 26 designs. That may fit the bill.
A further OMT refresh of the RAN Iver proposal for the RNZN should not be shatteringly expensive in terms of billing hours (as naval architects they will make their coin in the royalties, design transfer and licensing of the build). With the hull built and foundational machinery installed in a SK contracted superyard like HHI at Ulsan, with the CMS, radar, sensor, asw, weapons fitout (other than RIM-116 dumped for CAMMS) of the FFG(X) from LM and Raytheon as sole source providers and integrators, it may end up being more expensive than a UK built Type 31e Arrowhead but it would be substantially more capable and close to the performance of the FFG(X) and yet less expensive than the USN platform.
If one looks at the possible future candidate frigate platforms for the RNZN from other 5 Eyes Navies (As the apple will likely not fall too far from the tree) we are left with one of the following:
The Canadian future surface combatant, the UK Type 26 and the RAN Hunter Class. Each of those three will be very expensive and would mean that getting a much needed 3rd Frigate would be much more difficult. Or the USN FFG(X) - cheaper than the first three but still not an inconsiderable cost NZ$1.2B, or the Iver based Type 31e Arrowhead, the cheapest and less capable offering - arguably not quite able to cut the mustard in a highly contested Indo-Pacific region post 2030. Finally the 6th alternative, my tweak on NG's proposal above, a refreshed Iver hull fitted with US sourced MTOS systems, sensors, weapons that substantially mirror the FFG(X) capabilities and can like the Hunter Class and FFG(X) connect, distribute and contribute with and for each other.
and I doubt the Navy or the Govt would be too keen on having the only examples of said frigate in operation.
The RNZN Anzac Class are now very different than other MEKO 200 hulls out there - the hull and COTS machinery is the basic bit. It is the CMS, sensors, radars, weapons fit out that are widely different, the bespoke part, the business end. Our post FSU Anzacs are closer to the Halifax Class in that regard than the RAN Anzacs. They seem comfortable with that.