Not really sure I follow the logic, since you'd expect to find the names of countries in local languages to be different.
Sticking completely to English, take the case of Ireland:
Ireland has two official languages: English and Irish and all laws + the constitution is published in both languages, with Irish taken precedent in cases where the English version is unclear.
The constitution states that the name of the country is Ireland in English and Eire in Irish, so far so good. This means that there is no such country as the Republic of Ireland, it's the name of the football (soccer) team! However there is a law that states that the "Description" of the state is: The Republic of Ireland!
And then there is the UK's Ireland Act of 1949, which has two interesting clauses:
- The name of the Irish State is Eire
- Irish citizens are not foreigners!
So you have the Irish Department of Foreign Affairs referring to the country as Ireland, while UK Foreign Office officials refer to the country as Eire (the Irish name!). And when it comes to discussing Irish affairs in Westminster it produces some of the most confusing discussing imaginable.