The Google list sections recognises currently only "Args", "Raises" and "Attributes" as headers for sections that consist of a definition list. This could be extended to recognise more section headers, similar to what sphinx already does.

The list of sections that sphinx supports is quite extensive, but I'd suggest at least adopting "Keyword Args", "Keyword Arguments", "Yields" and "Examples". The "Yields" header is specifically mentioned by Google as an alternative to "Returns", and I have seen "Examples" mentioned in older versions of the style guide. The keyword arguments are not specified by Google as such, but are widely used.

There are also other list-type sections on the Sphinx list, so implementing as much as possible would improve Sphinx compatibility a lot.