Hi Venkat,
I am not sure if you are still looking for an answer but posting as others might benefit out of this.
We are using DL classic in a multi project/environment setup and I don't think there is a direct way to achieve what you are asking for.
We maintain a table ( outside Apptio) which has all the attributes required by DL classic to create a connector and then using APIs we create the required connectors. You can get in touch with Apptio experts to guide you on how to connect & create connectors using API.
I believe that's the only way to do it in bulk otherwise we will need to create connectors manually.
Experts - Please add if I have missed anything.