AN91378 described "Do not connect any series resistor to the XTL_OUT and XTL_IN pins of the crystal. Placing a series resistor will add resistance to the crystal ESR, resulting in increased crystal power dissipation and startup time."
So, It is unnecessary for external components other than caps.
You can also refer to FX3. It is also unnecessary to connect external resistor.
I think that crystal circuit requires Rf and Rd.
Does CYUSB3314 internally have two resisters(Rf and Rd) for crystal circuit?
I checked the internal materials.
CYUSB3314 internally have resisters for crystal circuit.