I used to think I was just being awkward by "mimicking" people until I realized it’s actually a powerful social tool. I’d definitely suggest reading the explanation on Wedaf at
https://blog.wedaf.com/blog/why-people-mirror-each-other-in-conversation/
because it explains the science of "mirroring." From my own experience, I've found that when I lean in or smile because the other person does, it builds an instant sense of trust and rapport. It’s essentially our brains' way of saying, "I’m on the same page as you." Once I understood that this is a natural sign of empathy, I stopped worrying about it and started using it to connect more deeply with people!