You can safely use any Unicode character including emojis on your custom labels. Emojis are great ways to draw more attention to stock labels.
The Customization Options Chapter from the Full Product Walkthrough Video:
In the same label customization section, there are "Translations" icons for each stock label category. Click to open translation pop-up for this particular category (In the example, "High Stock" category):
You can add, update, remove and manage translations for each stock category easily in this pop-up:
To add a new language translation for this label, click "Add Language" dropdown and select the language you want to add. A new row will be added to the form above with empty text box. Enter the translation for that language, close this pop-up and save settings.
Translation Options Chapter from the Full Product Walkthrough Video:
Translations of labels will be automatically shown based on the Shopify language/locale setting selected on the shopper's session.
Shopify does not come with language selector out of box and store owners enable this capability with theme customization or 3rd party apps that allow shoppers to switch languages. All of these apps work the standard way Shopify operates with multiple languages.
Note: There are 3rd party apps and themes may work out of this Shopify standards. Translations in Product Stock Status Label app does not support custom language implementations. Please reach to support at if you have issues with translated labels not displayed correctly in your store.