If the intent is to secure the connection, then we would suggest using TLS rather than just TCP service in Tyk and maybe use client certificates to identify users and grant/deny access.
Or you can you use your own custom auth plugin instead.
The use of client certs and TLS is generally dependent on the capability of the client app.
If the intent is to take the data (Headers and Body) and forward the same to a TCP Port, then I don’t know how achieve that unfortunately