xlSlim always tries to simplify working with Excel and Python. Adding a right-click context menu like this Plot menu should be easy.
However Microsoft, and our competitors, require an XML document like this to specify that context menu:
We think that is too hard which is why xlSlim 2.1.0 has added support for updating context menus with simple Excel function calls like this:
Ribbon menus can be added in exactly the same way.
Full details are in the docs