To record inter-branch transactions, you need to assign the appropriate voucher series to the branches that are involved in the transactions.
To transfer stock between branches, you can use the “Stock Transfer” voucher. Just choose the Material centre that matches the branch. This works if you are using the multi branch feature.
However, if you are using the Head office & Branch office feature, you cannot transfer stock directly from one branch to another. You have to first transfer stock from the branch office to the head office, and then from the head office to another branch office.