Having flown DUB-AUH-SYD last year, I can confirm the DUB-AUH segment booked as a VA flight number but operated by EY earns 0 SkyMiles. You also get 0 privileges based on your DL status - no lounge access, preferred seating, priority boarding, etc.

That said, Etihad was a great experience onboard. (Not so much in Abu Dhabi - the airport there leaves a lot to be desired, particularly in terminal 1, until their renovation opens in a few years.)

The only time DL elites receive lounge access when flying VA is if they are in confirmed business class, or if they are at a lounge owned and operated by Virgin Australia. (I suppose there is a small chance that you might get access in LHR if there is a Virgin Atlantic-owned lounge in the same terminal the EY flight departs from, but I wouldn't count on it.)