The Welsh international, who joined West Bromwich Albion from Cardiff City last season, would be allowed to leave the Hawthorns for around £3million.
Earnshaw, who was the Baggies' top scorer last season but has been out of favour recently, has twice had requests for a transfer turned down in recent weeks. He is also reported to have asked FIFA to look into his £3million move from Ninian Park.
The diminutive goalscorer has been targeted by a number of Premiership clubs including Wigan Athletic and Birmingham City and, although not in the same target man mould as Dean Ashton, would represent something of a coup for Nigel Worthington.