By far, the easiest way I know of is to view all keybindings in a browser.
Assuming that your browser can display local xslt documents (e.g. Firefox), you can hit “Preferences > Keys > Print” and use text search for that purpose.
If you really want to dive into a Lua API tool, check out my vLib tree component - it supports loading of external XML documents, but you will need to come up with the rest yourself.
https://forum.renoise.com/t/new-library-3-0-vlib-a-ui-library-for-renoise/43884