Service Virtualization

Is there any way of changing the ENDPOINT value other than just making the change in the project.config?

Because in our existing tool, we have a option "Switch to environment". when we click on that option , it will show us different servers and Port and we can select the appropriate server and port and then all over testcases will run in that endpoint.

Could you please let me know, Is there any way in DevTest other than adding endpoints in project.config?

You can use create multiple configs with different endpoints and deploy your tests/Virtual Services.

Please refer Configurations - DevTest Solutions - 10.2 - CA Technologies Documentation.