Xbox one x audio out IR?

Hi. If Xbox One X doesn't feature it, then it's not possible for the Xbox One X. Most likely, that IR audio out is for Xbox One and Xbox One S.

IR out: Infrared output port for IR blaster (optional; IR blaster not included).

The IR port is designed to control devices via an IR transmitter such as a home theater system.

IR extension cables etc.

Do you mean the SPDIF Out?

Hi, if it is an Original Xbox One you would need an IR blaster, like the one built into kinect. If it is an S or X the IR blaster is built in.

I haven't checked on the newer Xbox One models (i.e. the S and X models), but the original Xbox One had an IR extender plug on the backside, where you could connect an IR Extender, and run the cable inside a cabinet to control the devices that are otherwise
unreachable for the IR signal sent out by the IR blaster of the console or Kinect.

If your console has such an IR extender plug, you can simply use such an extender and route the cable for that extender from where your console is to near the IR receptor on your TV.