How to import subscribers from other plugin/ service (Or WordPress) to Email Subscribers?

Step 1 : Install WordPress Importer plugin

Step 2 : Export subscribers list of any other plugin (or WordPress users) using WordPress Importer plugin

Step 3 : Make sure it has CSV format as specified above

Step 4 : Go to Email Subscribers -> Audience -> Import

Step 5 : Import the CSV file that you have

That's it! You have moved your subscribers' list to Email Subscribers.