The France international returned to Old Trafford in 2016 but is rumoured to be unhappy with his situation and has spent much of this season out injured.
With United said to be torn over what to do with Pogba, Shearer told The Sun: "My guess is United will cut their losses and try to move on from a four-year spell which was not what either party planned.
"I think he probably feels a little bit let down by what's gone on at United. It's a mess on both sides."
The former Juventus midfielder joined United for around £89m and has since been linked with a move to Real Madrid.
In 143 appearances over his second spell at the club, Pogba has scored 31 goals and won the EFL Cup and Europa League.