Regulate/regulator are not appropriate replacements for manage/manager in business. The only use I can think of for regulate/regulator applies to an external organisation having some element of control over how a company operates. For example, in the UK, firms of solicitors are regulated by the Solicitors Regulation Authority, or Charities are regulated by the Charity Commission.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.