When swapping a non standard character, all expressiveness values become 100% on the character.
With a non standard character when you swap it for a different non standard character all expressiveness values are at a 100% on the character even as the values on the face key panel expression values is correct.
To make the character match the values of the keyframes, I have click on every expression keyframe with the face key panel opened and change the expressiveness up 1 then down 1 for the character to have the have the correct matching expression value.