Yes, the Magento 2 Marketplace vendors can add a video along with the product images under their own account panel. For this, the marketplace admin needs to enter his YouTube account API Keys in the admin back-end panel by navigating to Stores->Configuration-> Catalog->Product Video. Here, the admin will enter his account(YouTube) API key and then save the configuration.
After this, the marketplace vendors are able to see the “Add Video” button on their add product page.
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