Other people's voices
I'm very susceptible to how other people talk. I pick up someone's accent, phrasing, word choices, and so on. Really quickly. In a single conversation. To the point where I have to be really aware of it and hold back, worried it might seem mocking.
Other than worrying about that it's mostly a good thing.
In a rare moment I'm going to say I'm fairly solid at writing dialogue. My dialogue gets pretty good feedback and I feel it's a strength. It's usually the easiest and first part of a story that comes to me. My 'scraps' documents are just full of dialogue.
Once I've heard someone talk I 'hear' their written communication in their voice. Writing fanfiction of visual media the characters are just chatting away in their own voices.
Given the places I've lived, all my life I've been surrounded by people for whom English is between a second and a fifth language. My home town, then Wales, London, now back home. I've been told I'm good at understanding people with limited English - by both those people and observers - and that feels true because it never stresses me out or feels like a problem.
I'm extremely used to the very fluid way people flow in and out of languages in a single sentence and use context to just figure it out. Or be okay with not knowing. Just letting it wash over me. I'm also very used to other languages being spoken around me. This bothers some people, or so I understand. Though I don't understand why. It doesn't bother me to the point I rarely even notice.
At university I walked home from a lecture with a friend who was on the phone. She then apologised to me for speaking Welsh. Honestly, I told her, I didn't even notice. Also at university, friends were having a full-blown conversation, in Welsh. Said something to me, still in Welsh. I turned round and switched the light on. As instructed. Everyone was like "?" It must just have been context, some hint of intent, I don't know.
The really useful way this should manifest is being great at learning languages. Unfortunately, I am not. Though I can swear in several languages of the Indian subcontinent, do basic greetings, introduce myself, numbers to about ten, and have some slang in a couple of what we would call 'community' languages, including Welsh.
My own accent is a mess, fully an amalgamation of everyone I've ever spoken to in my life. It's not particularly recognisable as local - people from my home town are generally surprised to find I'm from there. It's broadly 'the Midlands' but much of my vocab and speech patterns are more northern because of my wife and my parents. Under stress I become more Yorkshire.
My mum called me a mimic and I don't think she meant it as a compliment. But I took it as one.