Can I gift Diablo 4 and VOH to a friend and still get the rewards for wow?

[Bertheigh-korialstrasz (Bertheigh)]

no they would get the rewards not you.

Eligibility Question for Cross-Game Rewards

Received word back and yes, regardless of if you purchase the license or someone else gifts it to you, if you have both on your Battle.net account you’ll qualify for the promotional rewards once they come out. Note: The person gifting the expansion(s) does not qualify for the rewards with that purchase. They would also have to have those licenses on their account to qualify.