the euro coins (2nd type) have now letters showing which country they are from, but in my my opinion those letters are NOT mint marks!
Have a look at this: https://en.numista.com/catalogue/pieces13318.html from Finland
and also at this documentation

In my opinion the Finland example should NOT have FI as mint marks?
Andorra has no mint marks neither a country code
Austria has no mint marks neither a country code
Belgium had no mint marks neither a country code before 2008,

Belgium introduced the BE for BElgium in 2008 and has changed the mint symbols in 2013 from the feather to a sitting cat (I think?). In 2014 the two symbols (imperial orb / cat) exchanged places!
Cyprus has no mint marks neither a country code
Estonia has no mint marks neither a country code
France has mint marks. Cornucopia+Bee from 1999-2000. Cornucopia+Horse shoe 2001-02. Cornucopia+Heart 2003. Cornucopia+French horn 2004-10. Cornucopia+Pentagon 2011-2017
Germany has a D (as in Deutschland) as a country code, which should not be confused with the mint mark A, D, F, G or J!
Greece in 2002 had the 10 cents to 2 euro coins with and without mint marks, but there is no country code.
The Netherlands has no country code, but mint marks. Bow in 1999. Bow & star in 2000. Grapes in 2001. Grapes & star in 2002. Sails from 2003 to 2013. From 2014 no more mint marks?
Ireland has no mint marks neither a country code
Italy has a mint mark (R) and a country code (IR) and something I could imagine would be the engravers' symbols?
Latvia has no mint marks neither a country code
Luxembourg has no country code, but mint marks as shown in numista.
Malta has no mint marks neither a country code
Monaco has no country code, but mint marks (following the French I assume?). Numista has forgotten the mint marks.....
Portugal has no country code, but some initials not described. 2002-16:VS/INCM.
San Marino has no country code, but some initials ELF INC?
Slovakia has no mint marks neither a country code, but the engavers codes are present
Slovenia has no mint marks neither a country code, but the engravers codes are present
Spain has no mint marks neither a country code (crowned M?)
Ole