(Note: checkout isn't part of the export, since checkout translations are stored on Shopify's end)
You can export your translations for backup purposes, to translate your content using a 3rd party tool or to delegate the translation process to a translation service of your choice.
To export your translations click "Export translations..." in the upper left language drop-down:
After you've clicked "Export translations..." the export intro screen will show up.
Click "Start the guide" to continue:
Select your theme(s) that you'd like to be included in your export.
The theme contains static content like "Add to cart", "My cart", "Copyright", etc.
After you've selected your theme(s) click "Continue to next step":
Select the categories that you'd like to be included in your export.
The categories contain the titles and descriptions of your Products, Collections, etc.
After you've selected your categories click "Continue to next step":
Select the language that you'd like to export.
Tip: If you want to export a translation template that does not contain any translations and that you can use for any upcoming translations, simply chose your base language (Swedish in this example).
After you've selected the language to export click "Export translations" which will actually start the exporting process:
After langify has exported your content, you can chose the format of your export: