Jeff K

The MailChimp Importer is a WordPress plugin that can automatically import your MailChimp newsletters as WordPress posts. 
By using the WP Cron functionality it will automatically go out at the interval you specify and download the text version 
of your newsletters for you. Through the settings you can set the author and categories that get assigned to the post.
If you don’t want to import the newsletters but show links to the archives we offer a shortcode to do that. By placing [ mailchimp ] 
anywhere in your post or page it will use the settings and grab your newsletters. You can also override the settings by adding attributes 
to your shortcode.

MailChimp Importer

Automatically import your MailChimp campaigns into your blog posts. Select an author and categories for your posts.

EverPress

Xaver

Mailster Newsletter Plugin

Integrates Mailster Newsletter Plugin with Gravity Forms to subscribe users with a Gravity Form. 
Requires the Mailster Newsletter plugin and the Gravity Forms plugin
<blockquote>
This Plugin requires <a href="https://mailster.co/?utm_campaign=wporg&utm_source=wordpress.org&utm_medium=readme&utm_term=Gravity+Forms" rel="nofollow ugc">Mailster Newsletter Plugin for WordPress</a>
</blockquote>

Mailster Gravity Forms

Integrates Mailster Newsletter Plugin with Gravity Forms to subscribe users with a Gravity Form.

MailChimp Importer vs Mailster Gravity Forms