Joe Dodoo is yet to start a League One game in Charlton colours after moving on loan from Rangers in the summer.
Charlton defender Ezri Konsa has attracted major interest.
Karl Robinson has shared how he was prevented from signing Harry Winks at MK Dons.
Glasgow Rangers forward Joe Dodoo has left Ibrox for Charlton Athletic on a season-long loan.
Chris Wood has joined Burnley from Leeds United in the summer transfer window.
Charlton could face competition from Wigan Athletic for O'Shea, who helped Sheffield United to the League One title this season.
The right-back moved to Ibrox during last summer's transfer window but has appeared just once under new Rangers boss Pedro Caixinha.
Bradford City's out-of-contract winger Mark Marshall has been linked with Charlton Athletic and manager Karl Robinson has hardly dampened speculation.
Ibrox outfit Glasgow Rangers should look at former Gers player Alex Rae, suggested Charlton Athletic manager Karl Robinson last month.
The Charlton Athletic boss took a risk on the midfielder at MK Dons.