I'm the same way. Especially with facial expressions. Recognizing tone of voice/body language isn't as a much of a problem as facial expressions.
I'm also expressive with my face, though I have been told that I'm quite expressive with my mouth, and less expressive with my eyes, whereas NTs tend to be more expressive with their eyes. So for me, I think it's that my expressions are different from NTs.
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-Allie
Canadian, young adult, student demisexual-heteroromantic, cisgender female, autistic