Select File: Export: NetCDF to exports matrix sheet to NetCDF file.
When the data in the matrix is average across years, time is not be used as export to the NetCDF file. You can specify how to indicate time variable in the exported NetCDF file.
After get the analysis results from the NetCDF File, if you want to export it with the NetCDF file information.
You can try to right-click on the green Data Source Icon in the source data, and select Copy NetCDF Tree. Then right-click on sheet tab of the result, and select Paste NetCDF Tree to copy and paste the tree.
And then select File: Export: NetCDF to export result.