The Telling - S2-E22
Corrected entry: In the episode "The Telling" Syd wakes up in Hong Kong. When we first see her she is wearing a turtleneck sweater. When she is in the safehouse with Vaughn, the sweater no longer has a turtleneck, it is more scoop-necked. She did not have any clothes to change into, nor was she given any.
Correction: She probably was given the opportunity to shower and change by her handler. Just because we didn't see doesn't mean it didn't happen.