@olymay
Agreed, when using GMaps on watch much easier to start from phone as watch:
limited travel options i.e. cannot set it to do public transport. If i remember correctly it is only walk, cycle or drive.
the biggest issue is there is no search function, only a dropped pin option, so trying to find where you want to go is painful.
Otherwise you basically get same features as what is on the phone, including map, turn by turn directions.
So best option is to start it on the phone, which will then provide text direction notification on the watch, however when pressing on the notification it expands it and gives you the option of launching the watches GMaps app, which then loads in the full navigation (as per your phone) - or you can leave it as the text notifications…