According to this Official letter, in case a sub-contractor that is a domestic enterprise signs a contract with a main contractor that is also a domestic enterprise to participate in construction of factories, working office for an EPE, when the sub-contractor directly imports goods for construction for the EPE, it has to declare and pay import duty and value added tax.
If the sub-contractor has not yet declared and paid taxes at the importation stage, customs authority shall retroactively collect taxes and impose sanction.