"Dofollow" but Nofollow Case by Case allows you to selectively apply nofollow to your comments as well.
This picture shall give you an idea about Nofollow Case by Case. "Type" is what you do in your WordPress Admin within the comment moderation section. "Get" is what will happen on your website (front end) after saving the comment. If you do nothing you will have a dofollow plugin without any nofollow links in comments.