This doesn’t even matter for spouses as you can always elect to treat a foreign spouse as a tax resident under 6013(g) if they’re not resident or 6013(h) if they became a resident that year.
In this case 6013(h) allows the treatment of an NRA as a tax resident the year they become a permanent resident if they are married to a US citizen as of 12/31. Technically you have to attach a signed statement to the return by both spouses, but unlike 6013(g) I can’t ever imagine them enforcing that part of their internal procedure since it’s a once in a lifetime election and if they ever decided to audit you ever all you’d have to do is file an amended return with the signed statement.
OP — if you want to cover all bases upload a statement signed by both of you stating that you’re married and the LPR started the year as an NRA, ended it as a resident, and you’re jointly electing to treat the LPR spouse as a tax resident for the entire year under Internal Revenue Code 6013(h) for the purposes of filing a joint return.
OnlineTax, FreeTaxUSA, TurboTax, etc. should have a section where you can upload statements/attachments with your return. I don’t think it’s necessary just because of how impractical ever enforcing that part of the IRS regulation would be, but it’d cover all bases.
The short answer is: you can definitely file MFJ.
This is not tax advice and you should consult a tax advisor if after your own research you are unsure how to proceed.