I received this reply now from DHL:
1)If it is the name of the company imports .must provide company chapter and document clearance this shipment.And must fill Taiwan address on Airwbill.
If it is the personal name import, need provide personal passport or ID COPY to assist in customs clearance.Whether it is a company or an individual import.Both need import declarations are required to apply import license.
2)Computers and smartphones basically import duty rate of 0%,
There will charge be business tax 5%.
And are the Ministry of Economic Affairs Standard Inspection Bureau and the State Communications Communications Commission signed the control.The use of the same item input shall not exceed two units, the individual amount is greater than USD1,000 must apply import license.
So it seems only a total of 5 % will be added, but import license needed.