Nope they're pretty identical.
if you take a closer look at the elves in game you will find that their face and arms look normal, while their abdomen and leg got that texture that makes them appear like they have affinity with forest and nature.
You are 100% incorrect
Just look at the upper body texture for Sabille's art vs Sabille's model. The art has normal skin, the game model has weird messed up scar tissue for skin. Chest, shoulders, biceps, forearms, the works.
3d modeling hasn't reached the point yet where it can match an artist's rendering in quality and detail--remember that the hand-drawn rendering is two dimensional, whereas the "3d model" can be observed in all three dimensions--she can rotate 360-degrees, or you can walk the camera around her in a 360-degree circle, etc. None of which is possible, of course, with a hand-drawn rendering, or, in a game, a 2d sprite representing a person as a flat 2d surface--like the drawing. 3d rendering is getting better, and I daresay it can look much better than what we see in the beta version here, but much of that depends on how the game developers intend for the game to render, etc.
Also, I have to say this because it's so obvious: Elves are not human, you know...;) In the mind of the people doing the modeling, it's obvious that they feel a slightly non-human look is "more realistic" for an Elf (Elve?) than the hand-drawn version--which you'll note is dressed, and has much more of her body covered, than in your screen shot of this game character.
At any rate, I would have no trouble ID'ing the game-character as the Elf in the rendering. I mean, the resemblance is close enough that even you have no difficulty in seeing her as an Elf...
Wanted to add that the only "plant things" I see in the rendering are the skimpy little plant things that she has so tastefully opted to cover up her...uh, herself with...
Which are vines and leaves, of course.