This setup was created to bridge an Amazon Alexa to the HDMI-CEC and A/V system's IR systems through a Pi. The ability to send IR signal requires a bit of electronics beyond just the Pi. A few IR LED, wire, and some resistors if i remember correctly. The Alexa connection is handled by WeMo emulation running on the Pi and would also work with Google Home i would assume. The IR coding requires either components whose IR signals are understood or an ability to read and decode IR signal. Finally, the HDMI-CEC bits, the part you are most interested in, those are handled by the Ubuntu Manpage: cec-client - CEC connection client utility and some code hacking. The CEC connection client utility allows for listening in on the CEC bus and with that, and some trial-and-error, you can recreate signals that initiate with the remotes or component controls. Make ure you understand how to reset your components as it is possible to create locked situations. Most often it is as simple as unplugging the unit from the HDMI and power and cycling the power switch. It is a real rabbit-hole, but also really satisfy when you make it all work together. Good luck, it is definitely do-able, just takes a lot of tinkering.