In order to configure the blog post author in Magento 2 Blog navigate to Stores > Configuration > Magefan Extensions > Blog and find the Author section. Here you have to choose whether to Display Author Information or not. If you disable this option no information about the author of the post will be displayed on the blog post page.
If you decide to display author information there will appear the following options:
1. Display Author Block which includes author photo, bio description, and social links.
2. Display Post List by Author which shows author latest post.
3. Default Robots which will be included before head closing tag in page HTML.
This is how the author's block looks like on the storefront when enabled.