Julian Lang

Send Denial – a spam sentinel
This plugin will enable honeypot and other anti-spam techniques (in future versions) to protect your business and mailbox from automated script spammers. In “basic” honeypot mode there will be zero impact on your users. they won’t see a captcha or puzzle to solve, they can just use your websites forms. Plug and play
This plugin will be compliant with GDPR guidelines as it won’t call external apis or databases at all. In future versions there might be a local database table (in your database) where failed submissions (from bots) will be stored so you will have total control over the data.
currently supported (protected) plugins include:
<ol>
<li>Caldera Forms</li>
<li>WPForms Lite</li>
<li>CF7 (Contact Form 7)</li>
<li>Ninja Forms (including ajax submissions)</li>
<li>Formidable</li>
<li>WooCommerce (registration, checkout, login)</li>
<li>Elementor Forms (Pro)</li>
<li>MC4WP</li>
<li>Jetform Builder</li>
<li>Ultimate Member (Registration Form)</li>
<li>FormCraft Premium</li>
</ol>
planned support for the near future:
<ol>
<li>bbPress</li>
<li>Divi Forms</li>
<li>Fluentform</li>
<li>HTML Form</li>
<li>Gravity Forms</li>
<li>BuddyPress</li>
<li>Easy Digital Downloads Checkout</li>
<li>Toolset Forms</li>
</ol>
This plugin will support as many popular plugins as possible for free. There is no intent to sell “premium” anti spam protection in the future. You can help to support costly formbuilders or other paid plugins by donating a little amout to help fund the licenses for the development environment.

Send Denial

Anti-Spam protection for the most popular and widly used formbuilders and plugins. GDPR compliant.

Denis V (Artprima)

AP HoneyPot WordPress Plugin, based on Jan Stępień’s http:BL, allows you 
to verify IP addresses of clients connecting to your blog against the Project 
Honey Pot database. Thanks to http:BL API you can quickly check whether your 
visitor is an email harvester, a comment spammer or any other malicious 
creature. Communication with verification server is done via DNS request 
mechanism, which makes the query and response even quicker. Now, thanks 
to AP HoneyPot WordPress Plugin any potentially harmful clients are denied 
from accessing your blog and therefore abusing it.
<h4>Your Feedback Matters</h4>
Bugs to report? Feature requests? Criticism? New ideas? We want to hear from 
you! Do not hesitate. Get in touch with us and share your views.

AP HoneyPot WordPress Plugin

Hard to believe I've been using this fro over 3 years, and the previous one before for even longer. No I wonder this is still being maintained, but still using in the meantime. 

Updated 3 years ago and still works great

AP HoneyPot WordPress Plugin allows you to verify IP addresses of clients connecting to your blog against the Project Honey Pot database.

Send Denial vs AP HoneyPot WordPress Plugin