However, this appears to be pure media hype. The sources involved have a reputation for unreliable speculation and on this occasion, it looks as though certain individuals are merely looking to fill up some free space in their respective papers.
Swansea fans shouldn't get too worried about this latest story, with Cardiff's reported interest linked to Earnshaw's own transfer to the Premiership. The stories have suggested that Cardiff manager Lennie Lawrence is interested in making Trundle his replacement, should the Welsh International leave within the coming weeks.
On the face of it, this move looks like one of the most unlikely of the summer period - Utter nonsense by people who have nothing better to do and will be laughed at by many Swansea and Cardiff fans alike.