Hello Amila,
As of now Data Driven Virtual services can be created only through DevTest Portal. Once created, you can download the VSI/VSM and edit in DevTest Workstation.
If it is a business requirement at your end. then I would suggest you to open an IDEA in this DevTest community mentioning the usecas and our poriduct management team may consider implementing it in future releases.
Regards,
Javed