right up one's alley

right up one's alley ( something that matches a person's area of interest or a person's skills; something a person should take a liking to based on their personality) — по его/ее/твоей/моей части; то, что подходит

Example: "Well since you're so flexible, Indre, yoga should be right up your alley!" — Раз ты такой гибкий, йога — это как раз по твоей части!

also
one's cup of tea

Example: "Baby-sitting? It's not my cup of tea/up my valley."

one's thing (one's interest; one's bag)
isn't my thing — не мое; не то, что меня интересует

Example: This isn't exactly my thing, but I'll give it a try. (Dictionary of American Slang and Colloquial Expressions by Richard A. Spears)

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Opp.
[you can count me out]
[outside sb's province]
[это не ко мне]
не по чьей-л. части