leticia

This very simple plugin allows multiple authors to be assigned to a Post or Page.
In admin panel, when you add or edit a post or page you can:
<ul>
<li>
specify additional authors, by selecting and adding them in the “Co-authors” panel. (See Screenshots #1)
</li>
<li>
put the shortcode “[sp-authors]” to display the list of co author’s links separated by comma.
</li>
</ul>
When the post/page is displayed to user:
<ul>
<li>you can see the list using the shortcode that can be added in the add post page</li>
</ul>
In any template:
<ul>
<li>
you can user the template-tag “sp_authors_display” to show the list of coauthors “display_name”, separated by comma
</li>
<li>
you can user the template-tag “sp_authors_photos_display” to show the list of coauthors avatars
</li>
</ul>
In search for author functionality:
<ul>
<li>the search take in care all authors, no just the user who write the post/page</li>
</ul>

SP Authors

This very simple plugin allows multiple authors to be assigned to a Post or Page.

Automattic

Daniel Bachhuber

Gary Jones

Mohammad Jangda

Assign multiple bylines to posts, pages, and custom post types via a search-as-you-type input box. Co-authored posts appear on a co-author’s archive page and in their feed. Co-authors may edit the posts they are associated with, and co-authors who are contributors may only edit posts if they have not been published (as is core behavior).
Add writers as bylines without creating WordPress user accounts. Simply <a href="https://github.com/Automattic/Co-Authors-Plus/wiki/Creating-and-editing-guest-authors" rel="nofollow ugc">create a guest author profile</a> for the writer and assign the byline as you normally would.
On the frontend, use the <a href="https://github.com/Automattic/Co-Authors-Plus/wiki/Template-tags" rel="nofollow ugc">Co-Authors Plus template tags</a> to list co-authors anywhere you’d normally list the author.
For more detailed documentation refer to <a href="https://github.com/Automattic/Co-Authors-Plus/wiki" rel="nofollow ugc">the GitHub Wiki for this plugin</a>.
Co-Authors Plus is an almost complete rewrite of the <a href="https://wordpress.org/plugins/co-authors/" rel="ugc">Co-Authors</a> plugin originally developed by Weston Ruter (2007). The original plugin was inspired by the ‘<a href="https://txfx.net/2005/08/16/new-plugin-multiple-authors/" rel="nofollow ugc">Multiple Authors</a>‘ plugin by Mark Jaquith (2005).

Co-Authors Plus

No support at all , also it doesn't work with wpml

No Support - Not compatible with WPML

Not working

Works!

I rarely ever give 1 star reviews, but developers who take over a plugin - making a breaking change that took a while to resolve - and then refuse to follow standard practice by providing a changelog (despite requests) for future updates, cannot be trusted.

Avoid at all costs.

Cannot trust developers

Assign multiple bylines to posts, pages, and custom post types with a search-as-you-type input box.

SP Authors vs Co-Authors Plus