This feature will allow the user to clear a specific sites data. Often you want to keep your cookies, cache, and/or history for all sites except a specific one. Currently we can only clear all of our data.
I believe this feature could be easily added to the site settings which are accessible when tapping the site’s icon when visiting it as in the attached screenshot. 
I have used a site and want all links to become unvisited and all customizations reset to the site’s default. Perhaps I’m having trouble getting new content due to the cache.
Safari implements this in Setting => Safari => Advanced => Website Data. There you can swipe left on any URL and clear all data for just that one site.