The Lions reportedly want a second-round pick for the former Rising Star winner, who played five senior games this season.
The 24-year old has played 112 games for the Lions since getting drafted with Pick 28 in the 2013 national draft.
Papley would be traded to the Blues for Pick 9 which would be forwarded on to Essendon along with pick 5 for Daniher.
Former Saints great Nick Dal Santo believes the Swans won’t give up Papley easy.
“If Sydney have brought in Lewis Taylor, that doesn’t mean they can afford to trade Tom Papley,” Dal Santo told AFL Trade Radio.
“He is the energy of their forward line, he’s almost the energy of their football club.”