Dabuuker

Show content in a modal after page load.
Usage:
Select ‘SN Popup’ from the admin menu, then Add New. Type a name for the popup and insert any content you like. If you’re done, click Publish.
Now find a page or post you’d like to see the popup on and edit it. There should be a new metabox called ‘SN Popup’, choose the settings you want and hit Update, then view your page.
Video: https://www.youtube.com/watch?v=t6lt6v3fuEQ
To change the styling of the modal, you can override its styles in your theme’s css. Or for more advanced styling you can dequeue the default css and replace it with your own.
For reference, the default unminified version of the css is located at /plugins/sn-popup/vendor/featherlight-1.3.4/src/featherlight.css
To dequeue the old css and enqueue your own, add something like this to your functions.php:
<pre><code>add_action('wp_enqueue_scripts','remove_featherlight_css'); function remove_featherlight_css(){ wp_dequeue_style('sn-featherlight'); wp_enqueue_style('featherlight-new-css','/path-to-new-css'); } </code></pre>

Soronet Popup

Piyush Asthana

Asap – Popups Studio lets you create and manage multiple popups from the WordPress admin. Each popup has its own settings for when and where it appears.
Features:
<ul>
<li>Multiple popups – Create as many popups as you need; each is a separate post with its own content and settings.</li>
<li>Display control – Enable/disable per popup; choose trigger (page load with delay, scroll percentage, or exit intent).</li>
<li>Visibility – Show on all pages, pages only, posts only, or selected pages.</li>
<li>Show once – Limit to once per session, per day, per week, or per month using cookies.</li>
<li>Custom HTML – Optional custom HTML (replacing the main editor content) with allowed tags only; no script insertion.</li>
<li>Animations – None, fade in, or slide up.</li>
<li>Width – Set popup width in pixels or percentage.</li>
<li>Quick toggle – Enable/disable popups from the list screen with a toggle switch.</li>
</ul>
For site-wide or per-page custom CSS, use the WordPress Customizer or theme/block editor. Uses the block editor (or classic editor) for popup content; optional custom HTML overrides that for a single popup. All user-facing strings are translation-ready (text domain: <code>asap-popups-studio</code>).

Asap – Popups Studio

Create and manage multiple custom popups with individual settings and display rules.

Soronet Popup vs Asap – Popups Studio