Spam to Spam box

Hello everybody good afternoon. I am posting this topic because I no longer know which one is best to follow. We have the configserver MailScanner tool installed on our server and working very well, we are identifying the messages as spam as we would like. Our problem is what to do with this message? Currently messages identified as spam have an identification in the subject line "{Spam?}" Or in the header. We were initially testing to identify messages identified in the subject, until it works at first, the problem is for forwarded messages ...... We were forced to look for a better alternative to this situation. Within the numerous possibilities we are looking at one would be the creation of global rules in cpanel to deliver messages to users' spam folder, in this possibility we are unable to edit a filter capable of delivering the message with a specific mark in the header in the spam box. of the email in question. After reviewing alternatives, I noticed that cPanel works with the "X-Spam-Flag:" flag and this is close to our custom flag. My question is ... what would be the best way to forward these messages identified as spam using a custom solution. We would not want to create custom rules for each email account (Although we have already been able to do this work via api) Is it possible to customize my exim to understand a second spam flag? Or change the default cpanel flag? (We have no intention of keeping the default cpanel flag active) Thank you friends.