Looks like the Garmin Fenix 3 (and HR version) are finally getting the audio prompts. Requires this beta firmware https://www8.garmin.com/support/download_details.jsp?id=9504 announced a couple of days ago.
These will probably further make their way to yet more devices, notably the 920. Often there is a significant delay.
Also, (Tobais again, ty) the data encryption also included in v3.3 (above) has been upgraded to handle the issues discussed here, probably.
Last Updated on 24 November 2020 by the5krunner

tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors.
The description for the update is odd because the Fenix 3 has had audio prompts (tells you your lap and pace each mile/km) through your connected headset since device software update 6.5. So I’m unsure what this update does. Also, what is the H3 version? Do you mean HR?