Translating the event template (Version 5)
The event template cannot be translated via a gettext editor (e.g. Loco Translate).
Update: Since version 5.1.9 Default Templates can be translated using Loco Translate or similar tool.
To translate the content, you will have to create your own event template via the builder.
1) Go to your Calendar Dashboard -> Builder -> Click the "Add template" button.
2) Select "Event layout" and leave "Blank template" unchecked to start with a prebuilt template.
3) Click the "Content Tabs" element to select it. Then, click on the cogwheel icon to access the settings.
4) On the left panel, you will find the Content Tabs settings, displaying each tab and its respective label.
You can assign an icon and label for each tab from that section.
5) After you have finished setting the labels, click "Save" in the top right corner and provide a name for your template.
6) Once you have saved your template, return to the Calendar Dashboard, then navigate to the Settings and select the Builder tab.
In the "Event template" input, choose the template you've just created.
And click "Save Settings".