Amend 2022 Return with new SSN

Yes, however if you file jointly (which was always an option, it just required an extra step) then you must report and pay US tax on all her world-wide income for 2022.   If she also paid income tax in her home country on the same income, the IRS will give a credit or deduction that should at least partly offset the foreign tax, but not necessarily completely.  Also, because the SSN was obtained after the tax filing deadline**, there may be certain tax benefits that she doesn't qualify for even if you file jointly.  (Possibly earned income credit, some education credits.  I don't know the full list.)  While joint filing has lower US taxes, if she had foreign earnings, the increased tax may offset the savings.  You would have to test it and decide once you see the numbers.  

**If you live in California, the deadline is November 16, so she would be eligible for those tax benefits–if any apply to her–if you mail your return before midnight on the 16th.