It doesn't seem clear what type of movement using Change Shape is. Action type is clearly defined, able to be upgraded from standard to move to swift.
The scenario is this: A Kitsune with Realistic Likeness is tied up while impersonating a big fellah. Not large size mind you, but big enough. He wants to use Change Shape to become that thinly built old man he talked to the other day to more easily escape the rope. Can he?
Next, assume his change shape is a move action.
Now what if it's a swift action with Swift Kitsune Shape Changer?
What about if he instead wants to use Fox Form?