Is this still not implemented? I tried some games that used this technique, and dint see any animations. Could this be emulated with shaders?
Correct we don't implement vertex blending (only some old cards offer it in hardware). It can be implemented using shaders. We would need to implement the whole fixed vertex pipeline using shaders. Stefan wrote a concept patch a few years ago but it had performance issues and he didn't fix those yet. Not sure if the code will make it in (it would require a volunteer to work on it).