Voice turn-by-turn navigation (with Komoot)

I have an Edge 530 and if I launch a course from the Komoot app I get voice guided turn-by-turn directions (voice comes out the connected phone). I can't seem to be able to do this on my Epix gen 2 despite the fact it's a much more sophisticated device.

If I sync the course to Garmin Connect and then duplicate the course then the watch will give me turn-by-turn navigation, but only with beeps. I have seen refences to people saying it does work on a Fenix 6 on this forum but no details of how.