If the character was yet another anonymous person who did porn to make ends meet during desperate circumstances, no qualities.
If it was BTL porn or an unpleasant fetish, then either Big Regret (if it is the character's dirty secret) or Bad Reputation (if the character's past is known).
If the character was an actual star, then Local Fame or even National Fame - remember that basic porn or sex work is not as stigmatized in the jaded world of Shadowrun.