Yes, because of Berne you don’t need to register copyright, and your copyright applies in all countries that are signatories. But it’s still national copyright

Yes, because of Berne you don’t need to register copyright, and your copyright applies in all countries that are signatories. But it’s still national copyright you are dealing with. As a German publisher, if an Italian publisher distributes a counterfeit copy of your book in Italy, you are in your right to send a cease-and-desist, but under Italian law, which just happens to be similar to the German one (because they are both signatories to Berne). If the Italian publisher doesn’t comply and it ends up in a lawsuit, it is going to be a lawsuit in Italy. If the Italian publisher also distributes the counterfeit book in Germany, you have standing to sue them in a German court (theoretically only for the copies distributed in Germany). As to the length of copyright, it’s not relevant if it’s a foreign or domestic work (that’s actually the point of Berne!)—you have to apply the length of copyright of the country you are distributing in. For a long time Canada had the minimum death + 50 years, which is 20 years shorter than most common death + 70 years. This did not mean that Canadian authors got 20 years less internationally. Rather, it meant that Canadian publishers could distribute any work, whether domestic or internationally, 20 years earlier than most other countries… as long as they only published in Canada. The Sonny Bono act similarly has no impact on the EU public domain, it was to prevent works to enter into the public domain in the US.