The following image shows Trixie's Corporate Goth uniform.
This outfit first appeared in the FGP episode "Gothic, Inc." Where she has to make herself work-ready for a school assignment to H.P. However, Timmy tries his best to sabotage it every step of the way.
Trixie also uses this outfit to defend her case against Timmy in "Gothparentless". Where Timmy tries to convince the Fairy Council (And Jorgen) that Anti-Cosmo, Anti-Wanda and Foop are NOT Godparent material. So learning Fairy Law from Foop, Trixie steps in as their defense attorney.
The outfit is a black and blue color scheme, with a chocker with the Anti-Fairy Logo on it. It also comes with a blue hair band, black glasses with blue-tinted lenses and a coffin-shaped briefcase with the Anti-Fairy Logo on it.