I think what you need is to use is IK on the legs.  Say you have a figure facing to the left.  With IK on, select the left foot and use the Xtrans dial to move it to the left.  Next, select the hip and move it to the left to balance the figure.  The next frame could be pulling the rear leg up, followed by again moving the hip to balance the pose.

With IK on, the body has to adapt to foot movements, and the feet remain motionless if other body parts are moved, including the usual main part, the hip.  I said to use the dials because I think you're talking about sliding type movements.  Of course, you can use the tools if you are careful.

Figure--Use Inverse Kinematics--check body part.  I hope this is what you were talking about.

John