I don't think this will work. Apple watch won't broadcast HR data to the Wahoo unit like a HR strap will.
To get the data into Strava with HR you'd need to be running the Strava app on the watch but it won't show on the bike computer. You'll wind up with two activities sync'd to Strava, then you go in and delete the non HR one. The only problem with this approach is if you have cadence/speed/power metrics running to the Wahoo as those probably won't pair with the Apple Watch. However I can't imagine there's any chance you don't have a HR strap but do have power meter.
JohnJ80- Polar doesn't broadcast HR, well not in any way you can get it to the Wahoo. The Polar Ignite "has" HR broadcast but it only works with Polar Club so its basically a gym/fitness class type of scenario.
Last edited by Laseranimal; 04-12-20 at 05:36 AM.