For a new plant while making Process Order (COR1), the batches are not picked up automatically despite the stock being available.  What need to be setup?

Make all these steps are done:

1) Spro--> Logistics - General-->Batch Management->Batch Determination and Batch Check-->Access Sequences

2) Spro--> Logistics - General-->Batch Management->Batch Determination and Batch Check-->Strategy Types-->Define Process Order Strategy Types

3) Spro--> Logistics - General-->Batch Management->Batch Determination and Batch Check-->Define Process Order Condition Tables

4) Define process order search procedure --> oplg

5) Assign search procedure & activity check --> corc

6) Define the class like fg / rm pm etc --> clo2

7) Define sort rule like fefo / fafo depending up on requirement

8) Access the transaction cob1 attach sort rule & selection criteria for all materials 

9) Check batch entry field in mrp 2 view
 

Batch no in process order 

How to do following setting :
1) Only manual allocation of Batch number under Good Receipt tab of process order should be done. i.e. No automatic batch number assignment under good receipt tab.
2) No release of order till batch number is manually assigned under Good receipt tab of process order.

First remove the automatic batch create from Production scheduling profile through OPKP or CORY.
Then Good Receipt Batch number mandatory through transaction variant SHD0

Or Use the Exit EXIT_SAPLCOBT_001 under enhancement PPCO0001 where-in based on your requirement you can create batch for your order. You can use CALL FUNCTION 'VB_CREATE_BATCH' to create the batchs as per your requirement.

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