How can I play League of Legends on EUNE using German client?

Solution 1:

The official Player Support page formerly said you can change the game language in a configuration file. This is still the case, even though it's not mentioned anymore.

Find your LoL install directory. The instructions diverge depending on what client you're using.

In the legacy client, go into RADS\system. Open the locale.cfg file and change the contents to locale = de_DE to change it to German.

I briefly tested this on the NA client with French, and it appeared to work fully.

In the new client, instead of going into RADS\system, go into the Config folder. Open the LeagueClientSettings.yaml file. Find the line that starts with locale: and replace it with locale: "de_DE". Be careful not to change any other lines in the file.

For more details, you can check out this post on the boards.