In addition, Caroline is obviously involved with the Salvatore Boarding School For The Young And Gifted, so even if she doesn’t pop up in the series in person, it would be difficult to get around referencing her.
In addition to Damon and Elena mentions, Legacies will actually feature Alaric Saltzman prominently.
Actor Matt Davis was at San Diego Comic-Con supporting the show this year and seems genuinely pumped to have a role in the new series.
Julie Plec also said during the panel that the door is open for any characters from The Vampire Diaries and sister series The Originals to show up in Legacies, so there should be a lot for fans who have stuck with the franchise from the very beginning to sink their teeth into.