I just tested this and was able to receive an inbound call as an agent. I then clicked "consult transfer" and dialed a flow by entering <flow_name>@localhost. The original caller was put on hold. The agent heard the call flow. I then clicked to "transfer" to complete the warm transfer. The agent was dropped from the call, and the original caller was left listening to the call flow.
Is that kind of what you were looking for?
Note, if you are calling a call flow that has spaces in the name, then you have to URL encode the space. So a call flow named "Default Flow" can be called by entering "Default%20Flow@localhost".