@pk
1. I have found no articulations either by the US treasury or the IRS regarding non-taxability of already taxed monies being transferred abroad, except for interactions with directly or indirectly banned / notified entities/ persons. Thus my position that transfers to your spouse or to a joint bank account in Japan is valid.
I think your answer may be confusing (it is to me).
As I read section 2523, a gift made to a spouse who is not a citizen, is subject to the gift and estate tax, regardless if the money was already taxed. The blanket tax exemption for gifts to spouses does not apply. In place of the blanket exemption for spouses, there is an annual exclusion limit which is $164,000 for 2022. Gifts over that amount are subject to reporting on form 709, and may be taxable if the lifetime gifts of the donor are more than $12,060,000.
So the gift is technically taxable, even though tax is rarely actually owed because of the annual and lifetime deduction amounts.
We have to make sure we are separating the ability to transfer the money, and the tax requirement. It is legal to transfer money; the taxpayer may be required to file form 709. The IRS will not jump in the middle of the transaction and collect tax, the reporting is "voluntary" or at least on the honor system.
