Get country name from a full address field

Hello, i have an address field in my base and i am looking to create some filters to categorise items by country, in some addresses i can see the name of the country at the end but others not,
here some examples :

Greater Milan Metropolitan Area
Warsaw, Mazowieckie, Poland
Paris, Île-de-France, France
Künzelsau, Baden-Württemberg, Germany
Stockholm, Stockholm County, Sweden
Geneva, Geneva, Switzerland
Vienna, Vienna, Austria
Greater Milan Metropolitan Area
Newcastle, Northern Ireland, United Kingdom
Ottawa, ON
Calgary, AB

Seems to be not possible by default in AT even with the map extension.