So, in the BlizzCon interview (like 4 months ago) with all the voice actors of Overwatch, Paul Nakauchi, or the official voice actor for Hanzo, had this to say on his inspiration:
I think Hanzo was very troubled by the fact he killed his brother. It pushes him forward, that’s his motivation for living. Kurosawa films were definitely an inspiration.
Now you’re probably wondering why I bolded his last sentence.
The person he’s referring to is none other than Akira Kurosawa. Now, you might not have heard of him before (If you have, you know where this is going!), but he is responsible for creating Seven Samurai. Do you know what proceeded it in a remake, 6 years later?
The Magnificent Seven. A western film that did equally as good as a movie.