Hi Manoj,
I dont know whether it is achievable by Functional Configuration. But technically it should be possible using Workflow. You can use the PR Created event of the workflow and create your PO since the PR will directly move to active status once you create as Release strategy is not defined.
I would say to look for some user exit if you can implement this logicwhat you are requiring.
Otherwise, you can fall back to Workflow as per what i was suggesting and usage of FM BAPI_PO_CREATE2 as raja was suggesting.
Rewards points if useful.
Thanks
Tirthankar