To work with Google Sheets, you would need to use their API.
This API is language agnostic and communication is via HTTP.
The tricky part then is sending the correct HTTP requests. You can use urlread to send HTTP requests or my FEX submission which gives you a bit better control:
That being said, you still need to implement OAUTH2, which is much easier than OAUTH1 but still not trivial.
On Windows you can use a program called Fiddler to observe the HTTP traffic between Matlab and any client you are sending requests to if you want to get a better feel for how HTTP requests work.
Ultimately I think the best way forward with this is to write a wrapper for the Python bindings. Interaction with Python is supported since Matlab 2014b.
