Hi Mariano,
There's an update regarding travel requirements!
Starting in March 2025, visitors must apply for an Electronic Travel Authorisation (ETA) to enter Northern Ireland. We have a
page with all the information about this new requirement and how to apply for an ETA to travel between Ireland and Northern Ireland. That being said, you do not need an ETA if you are only visiting the Republic of Ireland.
We hope this is helpful and would be happy to help with any other questions you may have!
Buona giornata!