I'm really not a developer, but this is something I expect not to be too hard to achieve :-) I really don't know where to start, so that's point 1. I read all of the topics about dynamically changing the widget title, but they all need human interaction.
Maybe I'm thinking too simple, but wouldn't it be easy to replace the default WOOCommerce Widget title (ie. "Product categories") by the parent category title?
Let's say that I'm browsing through the category "Nike" where I'm viewing products or categories, and the sub-categories are showing in the widget (ie. Shoes, Shirts, etc.). In this case the widget title "Product categories" should show "Nike" as widget title.
Could you help me getting it up and running?