I've just been having a bit of a laugh researching some of the classic championship manager players that were great / massively expensive in games of the past, but were actually pretty average / absolutely awful in real life. Here are some that I thought of, please add to the list!

Sean Dundee
http://en.wikipedia.org/wiki/Sean_Dundee
http://www.uefa.com/multimediafiles/photo/competitions/intertotocup/388527_mediumsquare.jpg

Florian Maurice
http://en.wikipedia.org/wiki/Florian_Maurice
http://images.chapitre.com/ima3/big1/881/7081881.jpg

Patrice Loko
http://en.wikipedia.org/wiki/Patrice_Loko
http://www.prostars.co.uk/localimages/players/large/644.jpg

Kennedy Bakircioglu
http://en.wikipedia.org/wiki/Kennedy_Bakircioglu
http://img230.imageshack.us/i/keneddyfxslwk7.jpg/

Rune Lange
http://en.wikipedia.org/wiki/Rune_Lange
http://www.hartlepoolunited.co.uk/javaImages/60/a5/0,,10326~5350752,00.jpg

Ruslan Nigmatullin
http://en.wikipedia.org/wiki/Ruslan_Nigmatullin
http://visualrian.com/storage/PreviewWM/0869/96/086996.jpg

Mads Jorgensen
http://en.wikipedia.org/wiki/Mads_Jorgensen
http://brondby.com/upload/biffile0_gsxuzablccwwjjwiu41g_42997.jpg

Johnnier Montano
http://en.wikipedia.org/wiki/Johnnier_Montano
http://lacuevadeldeporte.files.wordpress.com/2009/07/johnnier-montano-1.jpg

Erwin Avalos
http://en.wikipedia.org/wiki/Erwin_Avalos
http://www.clubcerro.com/Jugadores/2006/imagenes/erwin1.jpg

Kristoffer Haestad
http://en.wikipedia.org/wiki/Kristoffer_Haestad
http://gfx.dagbladet.no/pub/artikkel/4/43/437/437294/haestad.jpg

Stefan Selakovic
http://en.wikipedia.org/wiki/Stefan_Selakovic
http://www.dif.se/~upload/qpet_p.jpg

Tommy Svindal Larsen
http://en.wikipedia.org/wiki/Tommy_Svindal_Larsen
http://www.oddgrenland.no/pictures/p_1544.jpg

Porarrin Brynjar Kristjansson
http://en.wikipedia.org/wiki/%C3%9E%C3%B3rarinn_Brynjar_Kristj%C3%A1nsson
http://img89.imageshack.us/i/27627380wda4.jpg/

Cherno Samba
http://en.wikipedia.org/wiki/Cherno_Samba
http://i.dailymail.co.uk/i/pix/2009/10/20/article-1221790-0055BA1600000258-991_306x423.jpg

There's gotta be more, but I need a break!