This is not a huge issue, but something I found when reviewing this suggested edit (ensure you have
Wherever possible Stack Overflow is intended to be English oriented. Can we warn users when they input a link that has an obvious culture component to it? This is a simple mistake for an editor to make, and very simple for reviewers to overlook - however it could easily be detected with a regex either during the edit or at the time of submission.
A simple warning (rather than a blocking validation) should be sufficient - there is nothing wrong with a non English culture link especially if the author mentions that the target isn't in English (there will also be many occasions where there is no English version of the target page). I imagine something like this would be fine - although the color may need to change.