How to redirect an Internet traffic request for a specific port or program in a proxy server?

Question

proxy

Good afternoon. I would like to know how you can manipulate or redirect traffic for two different providers. I have things like this, at work there are two providers 1st provider ADSL unlimited channel width download / upload 8mbps / 1mbps, 2nd provider LTE 15 GB limit width 20mbps / 20mbps.
The task is such that from the second provider to skip requests from outlook / thunderbird mail clients or, say, on ports 25/110/587, etc. By what means is it necessary to do such a transfer of traffic or is it not possible, I did not find a suitable answer on google ???

Answer 1

And what about the proxy? This is not a proxy, you need a firewall that can do redirects. For example PF