If you want to use your Harmony and use the TV as the HDMI switching device, just update all your activities accordingly. Tedious but not terribly difficult.
Do your TV and Receiver both have ARC (audio return channel)?
If so, make sure it’s enabled. Connect the receiver to the TV using the ARC HDMI ports on both. When watching content on the TV with audio, the receiver should be set of the TV Audio HDMI port or however it’s labeled on your...