Create an email address that forwards to users in role

Your question’s answer is pretty long and it covers vast amount of tasks done. So it’s kinda pretty impossible to explain the full process with code here. I’m giving you some infos and advice here. Hope that helps you.

The steps needed-

  1. User Taxonomy: You can create user groups with giving them taxonomy based group relations like posts or any other post types. Here you’ll find a brief tutorial about it.
  2. Create Email Address: Hook in create user taxonomy. That means after create user taxonomy it’ll create a email address.
  3. Send Mail: Create a form which will tak ethe email inputs form user. Then sent it to all the user associated with the taxonomy.