Can we set up many sub accounts under one main external bank account?

We want to consolidate our many, many bank accounts. Many of
these accounts are for the same entity, but in reality it could be handled by
the same account. The only reason we keep them separate is so each of the sub
entities can only see and reconcile their own transactions. If everyone used
the same account, they all could see each other’s activity. This is similar to
banking done for a large retailer; WalCo has one depository account, each WalCo
store deposits money into the main WalCo account, but they have a store number
as a unique identifier. We want the same functionality; we want one main