Update: PTSB will still offer non-resident buy-to-let mortgages, as the income that will be paying for the mortgage will be generated by the rental income, which will be in euro, hence they don't need to be concerned with the currency in which the applicant is paid. They have extremely strict criteria around rental income, though, irrespective of the financial strength of the borrower. If the proposed rental yields are good, and you don't need a high LTV (70% is high - the lower, the better), then you could be ok.
Best Regards,
Dave Curry, Irish Mortgage Corporation
https://ie.linkedin.com/in/davecurryirl