Bon j'ai trouvé la solution pour celui qui a le problème:
Go into the Wasteland 2 save game folder:
Documents\my games\Wasteland2\Save Games
open up the XLM file and look for the characters name should be something like this:
<name>NAME HERE</name><displayName>NAME HERE</displayName>
then look for the character portrait, should be right next to the display name code:
<portraitName>PORTRAIT NAME</portraitName>
Where it says portrait name change to whatever your original file was called in the custom portrait folder.