No they will not. Devices manufactured with the intended market of retail distribution being Japan, S. Korea or any other country with laws requiring that imported digital cameras be made to permanently make the shutter sound, cannot ever have the shutter sound disabled.
So when Foxconn in China makes a run of iPhones, intended for shipment to Apple and Apple Authorized sellers in Japan, that run of iPhones is made with the shutter sound permanently set to “on”. It does not matter where those devices end up getting resold later as used devices, the shutter sound cannot be disabled, as was required by law for importation into Japan for original retail sale there.