This plugin was developed because I have one blog with multiple authors who have 
their own categories. The users’ category access is administered by the Authors2Categories 
in Tools panel of the admin.
Select the user. Click on Edit User (Tools>Authors2Categories) and select the categories he/she 
are allowed to post to. Click on Save when you are done.

Author2categories

This plugin was developed because I have one blog with multiple authors who have

flocsy

Authors Widget shows the list or cloud of the authors, with the number of posts, link to RSS feed next to their name, avatar. It is useful in a multi-author blog, where you want to have the list in the sidemenu. 
The widget can also display an “Author Cloud” if <a href="https://wordpress.org/extend/plugins/seo-tag-cloud/" rel="ugc">SEO Tag Cloud plugin</a> is installed.

Authors Widget

Authors Widget shows the list or cloud of the authors in the sidemenu.

Author2categories vs Authors Widget