Bulk editing of your eBay categories is available for needs review listings within the eBay channel.
To access the bulk edit tool, navigate to Listings, then select the Needs Review, then select the listings that will share the same eBay category.
Next, select Publish to eBay.
On the bulk edit page, select the Bulk Update button and select eBay Categories.
There are 2 available options
1) Choose to update the category for all of the selected listings, then choose continue.
2) Or choose to specify by category currently assigned. The first selection will be the category currently assigned to some or all of the selected listings. The second selection will set those listings assigned to the category chosen in the first selection, to the new category you've chosen in the second selection. Then choose continue.
Then you may edit the eBay attributes per listing, or if they're pre-assigned, simply select the update button.
When the update is complete, you're returned to the bulk edit page and you're able to view that the listings have updated to the new eBay category you've chosen. Then select the Save & Publish button to publish the listings to eBay.