For crossfading between poly channels, there is also Venom Poly Fade.
Turn off the internal phasor, and patch in a knob controlled phase signal into the phasor input. The envelope for the channels is configurable, as is the width (amount of channel overlap). You can overlap more than two channels at a time.
The Stoermelder Rotor can do the same, without the envelope shaping or width variation. But it requires a SUM module to combine the poly outputs into one crossfaded mono signal.
I am thinking of creating a 3-D crossfader (or morpher) with 8 mono inputs (with option for 1 poly input with 8 channels). It would have X, Y, and Z crossfade knobs and inputs to control the amount of each of the inputs in the output. If this already exists, then somebody tell me and I may reconsider.