You can update the inventory status labels through the language editor. Go to Online Store > Themes, click the ... button beside your theme, and choose Edit default theme content. Use the search bar to locate the inventory status labels and make the necessary changes.
For In stock labels:
For products with pending inventory transfers, search for the Back in stock text:
For out-of-stock products that can still be sold on the Online store, search for the Backordered, shipping soon text:
For Low stock labels:
You can now rephrase each label according to your requirements. Once you have made the necessary changes, click on the Save button to save your modifications.