Temporary Visa as director of investment company

I have a friend who is considering buying into my property investment company structure. My company is a Pty Ltd company.

The issue is the he is in Australia on a Temporary Business (Long Stay) – Standard Business Sponsorship (Subclass 457) Visa. This means he is allowed to do business in Australia and eventually apply for permanent residency.

I wish to know whether it is possible for him to become a fellow director of my company (ie. become my busines partner). I understand the risks of him not being a permanent resident/Australian citizen but am curious to know if legally possible to become a director while on the Visa?

Thanks,
Infinite