We would like any custom phrase that is created to be added automatically to "All Custom Phrases" in each installed language. It would be way easier to keep an overview of missing translations for custom phrases.
Official response
Hi Sandra, this is a great suggestion and has been implemented in the new version of our phrase translation functionality. Now when you create a custom phrase it will be available to be translated into every installed language pack on your helpdesk, minimizing the amount of work you need to do when creating custom phrases. You can access these custom phrases in Admin > Configuration > Phrase Translation and select the "Custom" tab.