Stunnel: How to forward client IP on Windows Server

Question

I set up stunnel on a Windows server.

Is it possible to forward the IP of the client connecting to port 6443 to the server on port 81?

This is my current configuration:

engine = auto
[MY_HTTPS_QUERY]
client = no
accept  = 6443
connect = 81
cert = SERVERCERT.pem

There ist an option called transparent but I think it's Linux only?

Thanks for your help!