See Tableau 2019.2 New Features for more details!
In Tableau Version 2019.2, we are releasing 2 new languages in Tableau. We are now including Traditional Chinese and English (United Kingdom) product language options in all Tableau products including Tableau Desktop, Tableau Server, Tableau Online, Tableau Public, Tableau Mobile, and Tableau Prep.
Please try it out and feel free to contact us at firstname.lastname@example.org if you find any issues with translation quality.
We'd also love to hear about your ideas for additional new languages in the future. Please keep adding your ideas and votes for new languages and international features in the Tableau Community Forums Internationalization space or by tagging your ideas with "INTERNATIONALIZATION".
Tableau Product Internationalization Team