"In every zone except the stack", including in a player's graveyard, "an adventurer card has only its normal characteristics" (C.R. 715.4). Thus, for the purposes of Traverse the Ulvenwald, while Lovestruck Beast is in a graveyard, it's a creature card and no other card types (C.R. 205.1a).
Will lovestruck beast count as a creature and a sorcery for delirium cards like traverse the ulvenwald?