Translation are now part of the OutSystems Data Grid Web Component.
 They are stored in an Entity named Translation that is Public but read-only.

To add or update translations to this entity use the public action: SetTranslation

To retrieve the translated value for a specific key there are two ways:
1. Server side: Using the public action, set as function, Translate.
2. Client side: Using javascript API: GridOS.TranslationsFeature.translate('[YOUR_KEY]').text
 
Check the sample below to set the values for the keys that are being translated in the grid header cells.
Change the values in the form and set the desired language in the dropdown to render the grid with the selected locale.