Currently Chaos Battle League only supports: 

English
French
Italian 
Russian
German
Spanish
Portuguese (Brazil)

You can play the game in any of these languages by changing your device to the supported language you would like to use and then restarting the game. After the game is restarted the new language will take affect.

Note: That in game News will still be in english regardless of the selected language.

Stay on the lookout for future updates with will included new localized languages.