Davidfor provided the right solution to your problem. However, I wanted to provide some screenshots too since the Calibre UI can be not so user-friendly, it's got so many options but knowing where to look for is the first step. First, as stated, you need the KoboTouch plugin. This should be straight, go to "Preferences"->"Plugins"->"Get new plugins", search for kobot utilities and install that plugin. After installing it or if you already have it installed then what you need to do is click the little arrow next to the Kobo Utilities icon to show the drop menu. There you have the option "update metadata in device library". If you are on the "Device" view the option will be greyed out, you have to be on the "Library" view for it to appear clickable and have your device connected. You also must have the books you wish to update selected before clicking it. Clicking "update metadata in device library" opens a new window with the option you are looking for. Check the "Date added" box and select what date field from Calibre you want it to be. In your case you would select "Date", which is the date added to Calibre, but it works with custom columns using dates too. From then on sorting by "Date added" in your kobo device will sort your books according to the parameter you selected, I particularly like setting it to the "published date" so I can have the books in my Clara sorted according to their publication date.