The concept is that the user can select one or more emails from which to send a message to one or more clients. It’s somewhat like an email campaign, but in this case, I want to send emails by extracting emails from an Excel database (which contains two columns: email and password) that will be used for sending (in this case, only Gmail emails) to one or more clients or their emails, also from an Excel database containing only client emails. The idea is to use Gmail SMTP to send emails. I’m not entirely sure if the logic is best implemented in that part. Is there even a possibility to create a plugin in this way?