It doesn’t appear that’s going to be possible from the information you’ve provided.
Your spouse is definitely eligible to apply for Irish citizenship via the naturalization process. You’re correct in stating that there’s a residency requirement – including the one year period immediately preceding the application period. That year must be spent by the applicant as a reckonable resident of Ireland.
As you say it’s not possible to leave the U.S. to complete this – that’s not surprising, of course – then your spouse won’t be able to apply for Irish citizenship at this time.
There are other rules for Irish spouses who would like to extend their Irish citizenship to a spouse. The marriage to the Irish citizen must be at least three years old before starting the process, and in addition to the one-year residency requirement just mentioned, the applicant must also have been living in Ireland for two of the previous four years prior to filing the application.
The couple must still be living together as husband and wife, and the applicant must be a person of “good character.” Also, Irish law says that the applicant must intend to live in Ireland after naturalization has been granted.
According to the Irish government website www.citizensinformation.ie, naturalization applications take about six months to process. And, as in the U.S., successful applicants are invited to take part in a citizenship ceremony to receive the certificate of naturalization. This certificate will allow the new citizen to apply for an Irish passport.
There are plenty of paperwork requirements of course. The website has full information for those who are interested.