Does FX3 support USB Video Class (UVC)?
Yes. The FX3 Software Development Kit includes the 2 UVC examples. One demonstrates the use of bulk transfer while the other demonstrates the use of isochronous transfer. Also, AN75779 includes an example on using UVC in FX3 for video streaming.
The CX3 can also be used to interface to image sensors which have MIPI interface and stream the video through standard video class. The details of how to interface CX3 to an image sensor is provided in the app note AN90369.