Re: Legal requirement
Hello there, and welcome to the Cove!
Let me preface this answer with the fact that I am not a lawyer, and cannot provide legal advice.
Are you referring to the legal requirement of you being a consultant? Or are you referring to the organization building the panels?
Understand I am basing these recommendations based on American practices, as I am not familar with other countries.
The National Electric Code provides oversight for performing electrical work, with exceptions. One of which is for a manufacturing organization that has UL (Underwriters Laboratories) approval. For the most part, NEC governs the electrical installations, and installing conductors from start to finish. If the company does not have UL and does not have licensed electricians performing work, other provisions include having drawings approved by a PE (professional engineer) to perform work.
Ok, I feel like I am rambling, and I am not sure if this is even close to what you are looking for. And again, I am trying to provide a general overview. If you are speaking about legal/authority having jurisdiction issues, you must consult local entities to find out what is involved.
Feel free to repost to provide a little more detail of what you are looking for.