UPDATE: Yandex no longer provides free API keys so DCS Rosetta doesn't work anyrmore. I don't have the time to look for a free alternative at the moment but might do in the future. Anyway, this is free software so if someone is willing to update the software, feel free to fork it or create a PR!
DCS Rosetta is a free application to automatically translate missions and campaigns for the DCS World flight simulator. It uses the free Yandex translation system.
You only have to do this the first time you run the program.
Go to https://tech.yandex.com/translate/ and apply for a free API key. You will have to sign up if you haven't done so before.
Once you have the key, select and copy it, and run DCS Rosetta.
Run DCSRosetta.exe and paste your Yandex key in the corresponding field. The application will save it for future use.
Load any DCS mission or campaign, select the appropriate languages and click on translate.
That's it! You just have to wait for a while.
The translated mission will have both the original and translated text inside. DCS World will load the most approapriate language based on your system settings.
Open an issue here at GitHub. I will do my best to fix the problem.
Google provides a more sophisticated translation service but it's not completely free. I actually wrote an implementation using Google but I removed it because of the limitations imposed on free users. I want the app to be consistently working as much as possible.
Yes. Just unzip the mission file like it was a zip file. Go to the I10n folder. Inside there is one folder per language. Go to the desired one and edit the dictionary file. Save the file, zip it and rename it to .miz again.
The process is similar for campaign files.
Not really... DCS Rosetta just gets the translated text from Yandex. But have a look at the previous question :)