Yes, vendors send mass emails to all the customers using Magento 2 Favourite Seller Marketplace Add-on.
After installing this module, the ‘Add as Favorite Seller’ button will be visible on the seller profile page and seller collection page.
Each vendor can check their follower list and send an email to all the followers.
Please do contact us for any further queries or requirements. You can also check our Magento 2 Extensions for additional features.