cPanel uses Exmin as mail server,
when sending an email via smtp/email client such as Thunderbird, Mail.app and outlook, a copy of sent mail is stored in local Sent folder but not on remote Sent folder (mail server). While when using IMAP it does because the client will be communicating directly with the server. google mail enabled this over smtp
Now what is needed, if it is possible if someone may possible stumbled up on the issue and found a solution to share it with us.