Perhaps! And I do fully support the kaldorei worgen allied race concept, that would be cool! But I have spoken on that already as well. Alpha Prime - who you see there in the scars picture - looks exactly like a normal worgen, and was in fact a night elf. Many of the Nightbane and Bloodfang worgen ingame were night elves, as well as the Terrowulf and Talonbranch worgen. Night elf worgen were also trapped in the corrupted Emerald Dream for over nine thousand years, with no side effects, and that is canon. However, there is one worgen ingame - Alton Redding - who has longer ears than are available to us ingame. So yes, night elf worgen canonically look much like normal worgen, though ear length could be advocated.
Worgen and the Nightmare came up recently on my questions thread as well.
Worgen and the Nightmare: Are they resistant? 
🥓 Worgen Lore - Ask me questions! - #151 by Raedolf-wyrmrest-accord
Honestly, yes! While these other options are already present and are logical, worgen are as they were designed to be, when it comes to limbs. For me, this goes back to their intention and creation in the narrative. The Pack Form was imperfect and unable to be controlled, and so - long story short - Elune blessed them with a form between man and wolf. What Elune provided was the perfect balance, that could be controlled if one could master themselves. Some lose themselves, while others maintain balance, something impossible for the Pack Form.
A tail is not part of that. A tail tips the balance in the direction of Gnolls, which are far more bestial. Scars and warpaint already exist, and need no explanation. But if one wanted to add tails, I would need a lore explanation for it. And if not, I would require tailed worgen that apply to my guild to pitch some kind of reason. There are a few possibilities as to how someone could grow a tail, and none of them are really great.