Steps to reproduce issue:

1. Create a Character Creator character with Expression Wrinkles enabled.
2. Confirm inside Character Creator that the wrinkle Normal and Displacement maps are working correctly.
3. Import the character into Maya using the Maya Auto Setup workflow.
4. Set up the Maya Arnold render settings according to the official tutorial guide.
5. Check the rendered result of the Normal and Displacement maps in the default neutral facial state.
6. Adjust and apply the facial expressions directly in Maya using the expression sliders created through Face Tools, then check the rendered result of the Normal and Displacement maps again.

Actual Result:
In the neutral facial state, both the Base and Wrinkle Normal/Displacement maps appear to render correctly.

For easier comparison, I attached the images below with all pores and fine details removed from the Base maps, so the pores and wrinkle details exist only in the Wrinkle maps and the Wrinkle Displacement behavior can be seen more clearly.

However, once facial expressions are applied, the wrinkle displacement appears to work correctly only in the upper facial regions, especially above the eyelids. From approximately the lower eyelid area downward, the expected wrinkle displacement no longer appears correctly, and it looks as if the Base Displacement map is being shown instead of the intended wrinkle displacement.

The affected range appears to be roughly from the lower eyelids down to the jaw area. Interestingly, the neck wrinkle displacement appears to work correctly.

Expressions related to Blink or Brows seem to work normally, but wrinkle details involving the mid-face and lower-face regions appear to be covered or overridden by the Base Normal/Displacement maps.

The most important clue came from the Cheek Raise expression. In this case, the wrinkle displacement appears correctly near the outer eye area, but from the lower eyelid downward it cuts off abruptly, and the result looks as if the Base Displacement is being rendered instead.

To verify this issue, I tested it across Maya 2025, 2026, and 2027, multiple versions of Auto Setup for Maya from older releases to the latest version, and multiple Arnold versions. The issue appeared consistently in all cases.

Expected Result:
The wrinkle Normal and Displacement maps should blend correctly across all facial regions when expressions are applied.

Wrinkle details for the mid-face and lower-face should render correctly according to the active expression, instead of appearing to be replaced or overridden by the Base Normal/Displacement maps.