Using HAProxy To Add Encryption To Outgoing Request

This is a bit of a strange situation, but I’m hoping someone here can help. I have an existing java application server and we are using haproxy to handle the routing. One of the applications is a legacy project that makes https requests to a third-party API.

The external API recently updated the security requirements for applications that want to communicate with it. I have (so far) been unable to successfully update our application to comply with the requirements. As an alternative, I’m wondering if it is possible to use haproxy to intercept the outgoing request and set the protocol and ciphers before passing it to the external API? If so, what do I need to add to my configuration to do this?