Damian Gostomski

The Imposter plugin allows site administrators to take on the role of another user. This is useful for development and testing purposes, as well as the ability to troubleshoot user issues without needing the user password.
It will add a link for each user in the users list, which will log the administrator as that user. They’re then logged in as that user and are no longer an administrator, until they logout of the user session, at which point they’re logged back in as themselves.

Imposter

Allows administrators to take on the role of another user for development, testing and troubleshooting purposes without knowing the users password.

konnektiv

This Plugin allows administrators to restrict user login based on user roles. This is useful e.g. when you want anyone to register on your site but you do only want certain people (e.g. editors) to enter the logged in area.
Roles that are allowed to log in are set in a new menu entry in the Users menu.
This plugin was originally developed for the <a href="https://quality4digitallearning.org/" rel="nofollow ugc">globe – Community of Digital Learning</a> on behalf of <a href="https://www.giz.de/" rel="nofollow ugc">GIZ</a>.
<h4>Contact</h4>
<ul>
<li><a href="http://konnektiv.de/" rel="nofollow ugc">Konnektiv</a></li>
<li><a href="https://github.com/konnektiv/restrict-role-login" rel="nofollow ugc">Restrict Role Login on GitHub</a> – Report issues, contribute code</li>
</ul>

Restrict Role Login

Allows administrators to restrict user login based on user roles.

Imposter vs Restrict Role Login