Set Category By Sender

Not sure what you are asking. The sender and “from” are the same.

I think you will find in the headers of emails sent from a google group that the from address is the individual who sent the email to the google group while the sender is the google group. Therefore, the sender and the from are not always the same.

@gnault You can do so by parsing the mail headers in postie_post_before hook and set the post category there.

Parameters:
$post
$headers

In your case $headers['sender']

Complete documentation here:
https://postieplugin.com/postie_post_before/

Thanks.