Winger Watt joined the U’s on a permanent basis at the start of the 2013/14 season after a successful loan spell and made 54 appearances in total.
Striker Ibehre moved to the Weston Homes Community Stadium, initially on loan, in 2012 and scored 17 goals in 76 matches. He also spent time on loan at Oldham and Barnsley this season.
Boss Tony Humes told the club’s official website: “It’s a massive shame that things didn’t work out differently with Sanchez because he is a player with huge potential.
“Unfortunately, we didn’t see his true ability enough and with his contract coming to an end, we had to make the decision to let him go and try and fulfill that potential somewhere else.
“Jabo’s contract is coming to an end and it has been clear for quite a while that he would be seeking a future elsewhere once the season had finished.”
Youngster Kevin Lokko has also been released, but the club are in talks with skipper David Fox over a new contract.