XLR to stereo 3.5mm cable?

Yes, the input will be stereo. The "Plug in power" thing is a facility to power small condensor mics, it's usually insufficient (2V or thereabouts) to power "real" mics, only those little hokey things that Sony makes. You'll definitely need your battery powered mic; It steps up the 1.5V from the battery to the correct bias voltage for the capsule.

You might also need to carefully tweak the gain settings (if any) on the camcorder. It likely also has an AGC which may or may not have settings to adjust. Sometimes you can also run into difficulty using balanced microphones with unbalanced inputs; Namely there's not enough signal present and the gain required to bring the level up also introduces noise. The fix for this is a little more involved - I built a transformer unbalancing box out of two old microphone transformers.

But, first thing to try is just the straight cable adapter:

Within the mic cable will be two wires (or two twisted pairs of wires) and the shield braiding. Wire one wire (or pair) to the tip of the 3.5mm connector, the other wire (or pair) and the shield should both be wired together to the sleeve. Then the ring (the third connection) should be shorted to the sleeve.

This is the bodgey way of unbalancing your mics balanced signal. The non-bodgey way involves a microphone transformer and will result in twice the signal amplitude which is often a necessity. But, try the bodgey (easy!) way first as it might get you by.

nifty