You can add hover titles to links created with Link Whisper from the settings. Inside the “Basic Settings” tab near the bottom of the page is the “Add Destination Post Title to Link” option.
Activating this will make the title of the page the link points to the hover title for the link. That way, when a visitor hovers the mouse over the link, the hover title will show where the link goes.
This title is inserted into the link when it’s created, so it’s there permanently, and turning off the option won’t remove the title. Activating this option also won’t update existing links.