Is there a way that I can allow someone to create and send a newsletter from the front-end, without needing to use the dashboard?
The person who will be doing this task does not need to use the dashboard for other purposes. Learning to navigate the dashboard just for this would be confusing.
Topic newsletter front-end Wordpress
Category Web
Perhaps a special 'contact' type form (like Contact Form 7) that is restricted to the specific user. They could fill out the 'message' area of the form, send it, and the back-end of the form would send it to your subscriber list.
Or the form could send it to you for approval, if needed. Note that this process is just a one-time thing; no storage of the content other than sending. (Although there are some CF7 add-ins that would allow saving of the content into a database.)
Added 26 Nov 2017: Check into the Email Subscriber and Newsletters plugin. It allows you maintain a subscriber list, and send out newsletters with a 'rich text editor' type interface. You can also set it up to send out a canned notice whenever a new post is published. I've just used for the 'new post' notifications, along with the occasional (one-time blast) newsletter. Good plugin, with good support.
Please Go through for this plugin. I think that use this plugin as per your requirement.
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