Thank you for the quick answer. I will be a little more precise.

I would like to forward https requests to different backend server based on the hostname header, e.g. https://machine1.domain.com should be forwarded to https://10.0.0.1 and https://machine2.domain.com to https://10.0.0.2.

You mentioned something like a tcp port forwarder. Is this tcp port forwarding part of the NGINX configuration or something outside NGINX?