If JLCPCB doesn't charge, you will get a bill from CBP, customs and border patrol. I've purchased capex equipment (items over $25k) from China for my small company and that's how we've paid tariffs in the past.
(Contrary to the current US administration's lies, the buyer pays the tariff, not the seller.)
(Contrary to the current US administration's lies, the buyer pays the tariff, not the seller.)