Shaharia Azam

Currently there are lots of plugins available to integrate 3rd party email gateway provider in your WordPress site. It seems that for every provider you need to install 
different plugin. From that use case scenario, this WP Mail Gateway plugin can be your All in One email solutions for WordPress.
With this one plugin, you can integrate tons of third party email service provider.
WP Mail Gateway can be your complete email solution plugin for your WordPress website. Send mail via multiple email gateway provider from your WordPress. 
Supports various mail provider. i.e: Amazon SE, Mailgun, Mandrill, Mailjet, Postmark, Sendgrid, SendinBlue, SMTP etc.
Currently we support the following email gateway provider. We are regularly updating the list.
Supported Email Gateway Provider:
<ul>
<li>Amazon SES</li>
<li>Mailgun</li>
<li>Mandrill</li>
<li>Mailjet</li>
<li>Postmark</li>
<li>Sendgrid</li>
<li>SendinBlue</li>
<li>SMTP</li>
</ul>

WP Mail Gateway

It's worth to install this plugin. In my case actually I have several email gateway provider for various reason (costing, spam protection, better deliverability, transactional).
So I can switch to my preferred email gateway provider for my Wordpress site whenever I want. I added and configured multiple provider and I can select which one will Wordpress use for email delivery. Simple and perfect!

It works. Superb! I can switch email gateway as I wish

This is the best plugin to use with Aws SES.
Contrary to what was mentioned, I found nothing wrong with the source code indicating some kind of scam.
Keep updating the plugin, note 10!

The best to use with AWS SES!

Send email from your Wordpress site via SMTP and other 3rd party mail gateway provider. Current it supports Amazon SES, Mailgun, Mandrill, Mailjet, Po …

Pascal CESCATO

Newsletter Optin Block allows you to automatically inject a Contact Form 7 form into your WordPress posts and add subscribers to a Mailjet list of your choice.
<ul>
<li>Select the Mailjet list in the admin</li>
<li>WordPress repository compatible (escaping, sanitization, etc.)</li>
<li>Robust API error handling</li>
<li>Works without Composer</li>
</ul>
External services: 
Mailjet API – allows: 
– fetching Mailjet contact lists (https://api.mailjet.com/v3/REST/contactslist) 
– adding a subscriber and returning a response code (https://api.mailjet.com/v3/REST/contacts)
<h3>License</h3>
This plugin is distributed under the GPLv3 license.

Newsletter Optin Block

Automatically injects a Contact Form 7 form into posts and syncs subscribers with a Mailjet list.

WP Mail Gateway vs Newsletter Optin Block