eBay is a great channel for auction style listings, but has recently grown to encompass new products as well.
If you have to create listings for thousands or tens of thousands of products on eBay, you should not be doing it manually! Instead you should employ eBay feed management, which can scale to thousands or hundreds of thousands of products with a feed based approach, and do optimization on product titles and other important attributes.
This can also save a lot of time on the eBay feed setup, where you won’t have to do categorization of products manually, but instead create rules to do the category mapping.