[Zubersoft]

I'm not sure what you are asking for here - the system file browser is Google's file picker. I don't have control over how that works. On my device, I bring that up, it takes a second to load everything, then I can tap the three lines at the top left and access any storage or apps on the device I want to that support Google's file picker. I can navigate through the internal storage and an SD card by picking those. You would have to use an app that supports saving a file through SMB for it to show up as an option. 

At some point I'm going to add SMB support in the internal file browser - I just haven't had time to work on that.

Mike