As pointed out you can use the Transition to/from in the WD panel but it is difficult to get this work very well. What I usually do is break the action down into two seperate movements, the walk and then the shift from final walk position to standing position. This is done by first completing the animation of the walk and saving the last frame of the walk as a static pose to the pose library. Reload the saved last frame onto the first frame to repose the character and visuall make sure that the positions for first and last frame match. Delete all key frames in between if they do. Decide how many frames you want to have the transition be (around 15 to 18 are usually enough) and trim the animation to this length. Go to the last frame and pose your character in the final standing pose and render the sequence. Clip it together in your video editing software for a complete animation.

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I don't fear God anymore. Anything he/she can do to me now is only adding insult to injury!