Forward/Redirect email fetched via fetchmail to gmail

I am on a mac using terminal. I am trying to redirect email from a work email to gmail (the work email only allows IMAP and gmail can only fetch from POP - hence the workaround). I have successfully configured fetchmail to fetch the mail from the work email. I would now like to REDIRECT it to gmail, such that when it arrives it appears to arrive from (and I can reply to) the *original* sender. I have tried both procmail and ssmtp with following configurations. For BOTH, the email does arrive in my gmail inbox however it appears to come from ME myusername@gmail.com rather than the original sender. Any suggestions? I am *very* new at this. Welcome suggestions using procmail or ssmtp (or if it will work anything else!) **procmail set up** .fetchmailrc file: set no bouncemail poll outlook.office365.com with protocol imap port 993 auth password user user@domain.com password password ssl sslfingerprint "" sslcertpath /Users/myuser/.certs keep no rewrite mda "/usr/local/bin/procmail -f %F -d %T"; .procmailrc file VERBOSE=yes :0 ! myusername@gmail.com (with sendmail configured to send from my gmail, as per my answer here: https://unix.stackexchange.com/questions/369842/using-procmail-to-forward-to-gmail/369854#369854) **ssmtp set up** /opt/local/etc/ssmtp/ssmtp.conf file root=FIXME@gmail.com mailhub=smtp.gmail.com:587 rewriteDomain= hostname=localhost UseTLS=Yes UseSTARTTLS=Yes AuthUser=FIXME@gmail.com AuthPass=Hunter2 FromLineOverride=yes (have also tried without root line, and with rewriteDomain=gmail.com) .fetchmailrc file, same as above except mda line is now: mda "/opt/local/sbin/ssmtp FIXME@gmail.com"