Wow, I'm not really surprised no one has responded to this question. I mean no offense, but your question is full or jargon and is hard to follow the real problem statement.
My first confusion comes your multi-identical professional? I have worked with many startups, some well funded, I have raised myself a few million dollar companies (not startups) and in all that time of dealing with many professionals in many industries I have never heard that term. But assuming it was just how it happened, if you are an experienced startup mentor wouldn't you know the answer to this question?

In any case, the answer to your question would be dependent on the focus of the startup what is the clear value proposition and the product offered? What is their growth path? business plan for revenue and even their marketing plan?
What are their current weaknesses - such as why would they need a mentor (specially maybe a paid one?)
...And then what are you core capabilities? or proven work and how can that be coupled with the gaps the startup has to achieve growth?
If you had good experience with startups, you would know that most good established startups with the right legalities typically give their board members and mentors anywhere from .05% to 5% stock for their services)

My name is Humberto Valle, I have worked with many startups from Arizona, to New York and SF as well as some in Portugal and Argentina. I currently run a global marketing agency that helps small businesses and startups with lead generation, growth, and custom software development. I have been mentoring for free for the past 10 years.