Great question.

I'd say a niche and a type are two separate things. Your niche is a certain topic, but your personality type is your motivation behind your content creation.

3 quick ideas to find your type:

1. Ask your friends which type fits you best in their opinion.

2. Try to emulate all 5 types, and find out at which one you are the most successful.

3. Who are your content creator role models? What is their content creator type?