higherfield

Kaigai Spam Mail Blocker is a WordPress plugin that automatically detects and blocks spam or abusive contact form submissions, especially those originating from overseas.
The plugin analyzes submitted content and blocks messages that do not contain Japanese characters or consist primarily of alphanumeric characters, which are common patterns in spam messages.
Supported form plugins:
<ul>
<li>Contact Form 7</li>
<li>Elementor Pro Forms</li>
</ul>
No configuration is required. Simply install and activate the plugin.

Kaigai Spam Mail Blocker

Blocks spam submissions from overseas contact forms. Supports Contact Form 7 and Elementor Pro Forms.

Sajjad Hossain Sagor

Block Spammy Disposable/Temporary Emails To Submit On Ninja Forms. Filtering Spammy Emails Will Increase Your Real Subscriber List.
<h4>Features:</h4>
<ul>
<li>Easy As 123, Just Plug & Play</li>
<li>Toggle To Enable/Disable For Individual Form</li>
<li>Translation Ready</li>
<li>Set Disposable/Temporary Emails Found Message (Default Message Provided)</li>
</ul>
Daily Hundreds of people submit emails to get free stuff but most of the time they use spammy disposable/temporary emails to get them… but now you can prevent that from happening. You can use this plugin to block/prevent disposable emails like 10MinuteMail and GuerrillaMail from submission on any Ninja Forms form.
Credits 
– https://github.com/andreis/disposable

Disposable Email Blocker – Ninja Forms

Block Disposable/Temporary Spam Emails On Any Ninja Forms From Submitting.

Kaigai Spam Mail Blocker vs Disposable Email Blocker – Ninja Forms