Quanon

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The ones I can think of that are definitely not the original head mdl are:

(numbers are based on this image, but might not correspond to the file names)

brown 2, Kazerian 1, Kiffar 3, all 3 Miraluka, all 4 Rattataki.

If there are any others that are changed, it's probably to make the uvw map match the texture better (like the hair of Asian 3 & Echani 2).