For the online courses from accredited colleges, I had checked the qualifications for hiring and for most courses, online or not, required a masters.
For the online and instructor led courses for adult learning (such as grant writing or event planning type courses), I find that all a person has to have is an interest in teaching the course. No scientific research, one of our board members was looking into teaching a class.
Some college websites may contain information about some of the professors, but not all.