Hi ,
You can still establish the connection between the two systems at ABAP level (ie an RFC) and bring the data from SAP BW on traditional to SAP BW on HANA.
I would suggest you build your new BW system based on LSA ++ and bring the data from the source to the BW on HANA system and not transort the data flow from old system. It is upto you . If it were me, I would not transport the data flow instead I would look for options to benefit from SAP BW on HANA modelling.
Best regards,
Magesh
