You need to get qtcreator program here:
https://www.qt.io/offline-installers
Qt Creator
Qt Creator 10.0.2 is released and it is available via Qt online installer. If you need a standalone installer, please select the file according to your operating system from the list below to get the latest Qt Creator for your computer.Qt Creator 10.0.2 for Windows 64-bit (273 MB) (info)
Qt Creator 10.0.2 for Linux 64-bit (192 MB) (info)
Qt Creator 10.0.2 for macOS (250 MB) (info)
After just click on qet_zh.ts to open qtlinguist program for translation.
https://doc.qt.io/qt-5/linguist-translators.html
