Willdial included a pdf tutorial for converting clothing for Genesis 3 & 8 in his updater application. Select the outfit and convert its rigging from General Weight to TriAx Weight. Once the rigging is converted, the outfit is saved as a Scene subset. According to the instructions, you need to create a Poser Companion File, which generates the CR2 file you could work with in CrossDresser.

These instructions were created using DSON Importer in Poser 11. Sadly, I have found that the application is not working for me any more in Poser 11, which indicates something has changed in the process.