The "crop factor" multiplier must be applied to both FX and Dx lenses to compare the field of view of a 35mm lens when used on an APS-C/Dx camera to the field of view of a 35mm lens when used on a full frame/FX camera. Both 35mm Dx lenses and 35mm FX lenses will give the same field of view when used with an APS-C/Dx camera.
This is because the focal length of a lens is defined by the distance behind the lens' entrance pupil collimated light is focused. What changes between a full frame/FX camera and an APS-C/Dx camera isn't the focal length of 35mm lenses, it is the angle of view provided by the size of the sensor.
The exception to this is when a Dx lens is placed on an FX Nikon camera. Because the light circle cast by the Dx lens is not large enough to cover the FX sensor, the camera automatically only records the portions of the sensor equivalent to an APS-C/Dx sensor. So in effect you have converted the FX camera to a Dx camera and thus the "crop factor" applies to images obtained with this combination.
If you place any 35mm lens on a Nikon D3300 (or any other APS-C camera with a 1.5X crop factor) you will get the same field of view as you would get with a 52.5mm FX lens placed on a full frame/FX camera.
If you place any 50mm lens on a Nikon D3300 (or any other APS-C camera with a 1.5X crop factor) you will get the same field of view as you would get with a 75mm FX lens placed on a full frame/FX camera.