Be patient, people. Apple is working on it. Sequoia 15.1.1 does indeed add the Hearing Health pane with Hearing Aid toggle. The ability to add Hearing Test audiogram setting is not yet working but at least the control pane lists it and has toggles for it. So I'd bet the functionality will be there in 15.2, at least for those of us in USA.
Meanwhile, it appears the audiogram settings reside in the APP2 and it absolutely DOES work when listening to audio on the Mac. Go set up Hearing Aid on your iPhone or iPad and enjoy audiogram-corrected Music on your Mac. Your personalized equalization. Pretty cool!
Connect to your APP2>Settings>your AirPodPro2>2/3 the way down find Hearing Health>Hearing Aid and toggle it and Media Assist, Adjust Music and Video on, etc and there you go.