I have found a way to bulk add the New Label to products by using Advanced Bulk Editor. I added a custom field for the label and made it a checkbox.
The new label option has been activated in the products that i tested it on, but unfortunately although the label appears on the products. I cannot seem to add a product carousel or grid that uses the data source Products with New Label. When i do try to use that setting it only display’s two of the Products that have the New Label.
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