Separation of channels can be done in VP.
Right-click the audio clip, UNlink FROM VIDEO.
Right-click the audio clip, then COPY.
Move the scrubber (red line) to the head of the clip, right-click and PASTE AS OVERLAY.
Click FX on one channel, click the green + cross and apply the PAN effect full left.
Do the same on the other audio channel and apply PAN far right.