Elementor

<p>Temporary Login creates a secure, temporary URL for easy access to your WP admin with no username and password. Share this URL with trusted support agents and colleagues in order to resolve issues quickly, and shut down access as soon as you’re done.</p>
<p><strong>FEATURES</strong></p>
<ul>
<li>Grant access to your site with a single click; a temporary URL will be created that you can share for admin-level access to your site and it will automatically expire 7 days from creation.</li>
<li>Extend access – need more time? No problem. Just click to extend access so that users don’t get locked out.</li>
<li>All done? Revoke access and the link becomes inaccessible.</li>
<li>Auto disable access – whether you forget to revoke access or lose track of the timing, there’s no need to worry. We will automatically disable the access URL at the expiration, within 7 days.</li>
</ul>
<h4>CONTRIBUTION</h4>
<p>Would you like to contribute to this plugin? You’re more than welcome to submit your pull requests on the <a href="https://github.com/elementor/temporary-login/" rel="nofollow ugc">GitHub repo</a>. Also, if you have any notes about the code, please open a ticket on the issue tracker.</p>


Temporary Login

Create a secure, temporary URL for easy access to your WP admin.

Denis Alemán

<p>Login Links allows you to create temporary, password-less access links for existing users or guest accounts. The links can be configured to expire either after a certain period of time or after a set number of successful logins.</p>
<h3>How Login Link Works</h3>
<p>A login link is a special link that, when clicked, automatically logs the user in. They don’t need an account. The login occurs either under an existing account or under a temporary account created specifically for this link. The link has an expiration date, after which it is automatically deleted.</p>
<h3>Provide Temporary Access</h3>
<p>Create a login link with a specific role for support teams, clients, developers, or guest users who need temporary access to the site, and email it directly to them. They don’t need to create an account or come up with a password, and you won’t have to worry about deleting their account later.</p>
<h3>Passwordless Access for Users</h3>
<p>Allow already registered users to log in without a password. Users request a one-time login link by entering the email they used during registration, and the link is sent to that email.</p>
<h3>Features</h3>
<h3>Temporary Login Links</h3>
<ul>
<li>Create an unlimited number of temporary login links.</li>
<li>Choose to log in as an existing user or as a temporary user, which will automatically create a temporary account attached to the link.</li>
<li>Delete and manage created links through a table interface, allowing you to view and remove links as needed.</li>
<li>Set expiration limits for each login link based on time or number of logins.</li>
<li>Expiration can be based on the number of logins, time, or a combination of both, whichever occurs first.</li>
<li>Send an email invitation with a login link.</li>
<li>Customize the email’s body and subject text.</li>
</ul>
<h3>Password-less Access</h3>
<ul>
<li>Allow password-less access for your users.</li>
<li>Custom login form via shortcode for password-less access.</li>
<li>Automatic deletion of expired links.</li>
<li>Automatic generation of a temporary account with a designated role upon link creation.</li>
<li>Optional password-less access through the standard WordPress login form.</li>
<li>Ability to disallow password-based access.</li>
</ul>


Login Links – Passwordless Login, Temporary Access Links & Custom Login Form


i tried two other plugins and they were limited to creating links for new users only. This worked great for my use case of sending creds to a client I had already created an account for. 



i think the popup modal with the new link might need some style adjustments on mobile devices. It was tricky to copy the entire link. A copy button would be a help... It might have been there just couldn't see the full width of the modal on my phone.


creates links for existing users

Create secure self-expiring login links for temporary access and guest users, and enable passwordless login for registered ones.

Temporary Login vs Login Links – Passwordless Login, Temporary Access Links & Custom Login Form