What? I've created three different fighting styles. A sword and shield style for Link from Legend of Zelda and both a single and backhand saber style for TFU fans.
Yes it is possible to make animations.
As for the other two arms, it depends on how they are created. I don't know how the four armed Grievous accomplishes his extra two arms. I thought they were sabers that were just positioned were his extra set was and would follow the same path as a saber swing.