The Castleford-born threequarter has inked a two-year deal with the ambitious Eagles, who will be full-time in 2016.
The 22-year-old made his Super League debut for Cas in 2012, and has since spent time with Doncaster, Huddersfield and Batley, before joining Fev in 2014.
“Like many of the players we have brought to Sheffield Eagles during the close season, Ben is another young and exciting prospect,” Aston told the Eagles’ official website.
“He fits the profile of the players we are wanting to work with, and like many who have come through the door, he arrives with a good background and plenty of potential.
“His ability isn’t in doubt and you know that because he was given an opportunity at Super League level.
“He has a good grounding and he knows what it is like to succeed at Championship level too. He has good experience for a player of his age and he knows what it takes to succeed in this division.”