You can make use of the Magento 2 Dropship extension, where in after clicking the importer icon will bring up this pop-up. Here, the admin will be able to make use of the Magento end attributes if already created or can make use of the new attributes at AliExpress end to Create a Swatch for which the admin needs to check the checkbox option. If the checkbox is selected then the attributes will be created under the name Capacity at the Magento end.

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