I am trying to figure out flow direction for a stream network and I do not have a high resolution DEM data for the same. I only have information about the stream orders and the network itself. Is there a way to figure out the flow direction based on stream-order connectivity as an inbuilt function?
I'm not sure of ways to do that without a DEM, however depending on the size of the project extent I would consider downloading a DEM from the SRTM site and running your analysis on that. The resolution will be approximately 30 meters but its better than not having a DEM