MailChimp Submission Form inside the Pop-Up Plugin
Avilable Pop-Up styles
With the CM Popup Banner for WordPress you can easily add subscription forms inside the popup. In each WordPress page or post you can add a particular banner fixed on the middle or bottom of the page or a post.
CreativeMinds Popup Banner Plugin for WordPress helps you add responsive popup banners to your site with custom messages and effects. Include images, videos and rich text in multiple campaigns.
Create multiple campaigns restricted by date, targeted to logged-in users and triggered by leave intent.
For more information go to the plugin product page
Here is the screenshots representing the setting of the campaign showing this popup banner