We have the heraldic ability and experience to develop, consult and decide on this. The Kingdom's chief herald has indicated that there no administrative problem with pre-registering several potential designs and names to "NZ Groups" against the possibility that one or more of them might be used after a formal Principality poll.
This area is often cited by groups as the most difficult/contentious point of going Principality, with tricky timing and sometimes significant delays in the process, so is something that should be tackled early on if a decision is made to proceed.
Preliminary names and designs could, for example, be informally polled for acceptance and registered as regional populace badges, or held for when required. A formal acceptance poll for proposed heraldry should happen as part of any formal bid process.
Earlier discussions have been held on possible registerable names for New Zealand, see this name subset and this much longer set canvassed in 2005-2008.
(See the winnowed set of name and device ideas recommended and surveyed by the Heraldic Working Group in 2023).