How to manage redirect in 3proxy using source address?

Question

proxy

Hello.
Tell me what you need to specify in the config so that 3proxy redirects connections of a specific user on behalf of a given IP address? IP addresses are listed as additional addresses (aliases) on the network card in Windows.
This is only necessary in order to implement the differentiation of users.
Then the traffic goes to RouterOS, and there it is marked and routed based on the address of the connection source.