This is an editor plugin to edit translation files from inside Godot Engine. It supports .csv and .po files, although gettext support is limited to what Godot can handle.
It can also be used as a standalone editor if `translation_editor.tscn` is run or exported as main scene.
This is a regular editor plugin. Copy the contents of addons/zylann.translation_editor into the same folder in your project, and activate it in your project settings.