The Team Showcase plugin is 100% translation ready and tested with plugins like WPML, Loco Translate, Polylang and most other multi-language plugins.
You can add translations using translation software like PoEdit. In the plugin folder navigate to languages and open awesome-plugins-team-showcase.pot with your translation software. Now start translating and on save it will generate a .MO file in the language that you created.
For example we created the dutch language version which is named awesome-plugins-team-showcase-nl_NL.mo new files will be named the same but with different language tags at then end of the filename.
If this was done correctly your translation should show up in WordPress automatically when you change the site language in Settings to the correct language.
If you want to learn more about how WordPress handles language translation then checkout this link: http://codex.wordpress.org/Translating_WordPress