It changes me in appearance (4)

I believe the answer is:

mien

I'm a little stuck... Click here to teach me more about this clue!

'appearance' is the definition.
(I've seen this in another clue)

'it changes me in' is the wordplay.
'me in' can be anagrammed to 'MIEN'.
However, I'm not sure how this is indicated.

Can you help me to learn more?

(Other definitions for mien that I've seen before include "Person's bearing" , "attitude" , "Comportment" , "aspect" , "The carriage" .)

I've seen this clue in The Globe and Mail.

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