Create New Company + New CoA and bring all the data and transactions from the old Company.

Our client is working with JDE, but they decided  to create a new CoA  plus new business units, the project scope is to change the  CoA over the same fiscal year 2019. One idea is to create a new company and try to bring all the data and transactions into the new one, maybe developing custom programs to mirror the old accounts balances Another approach will be using the global update tools for  Accounts, BU's, etc. (I guess this programs just works under the same company) Can you please share your thouhgts or if someone already deals with this type