It only allows to change Author to Guest and ad a name to the author, but it does not allow to add an Avatar (it's greyed out) nor a url (it's also greyed out) and in the post the "guest Author" name is not shown correctly but instead it shows the website's admin user.
In my case I needed something that would create the admin part an I can then use it on my custom theme. Definitely saved me some time to create my own custom meta boxes for the posts. Needed only to customize the single post template page to show the guest meta information.
This is hands-down the easiest to use Guest Author plugin in the repo, and has made this issue (public display of custom Guest Author names without creating dozens or hundreds of WP user accounts) super easy to address.
Found a weird bug in an edge case (ajax refresh within Elementor posts widget), and the plugin author responded + updated the plugin's code to fix the issue ASAP. Fantastic work!
A Great plugin!! The developer of this plugin is extremely supportive
The plugin had a small incompatibility with one theme and upon reporting it, the author went out of his way fixed it right away. Appreciate the great work and great support !!