connecting 2 ftdi cables together
If I connect 2 FTDI cables together reversing tx and rx would I end up with a usb to usb cable ?


Not quite. You would end up with a cable that could talk to the other end via serial.


  If so, I could connect a wireless FTDI adapter to a FTDI cable and get wireless usb.


No, you would have wireless serial via USB.


  Would I also need to alternat the CTS DTR lines ?


That would depend on your application.