The simplest way is to get both effect properties open in the timeline (corner pin with keyframe data & a fresh power pin) then one by one select each property of the corner pin and copy it onto the corresponding property of the power pin (Upper Left –> Top Left, etc…)
Make sure you’re at your first corner pin keyframe whilst copying, or it will paste offset to the timing of the footage.
Once done, disable or delete the corner pin effect, leaving the power pin with its pasted data.
Alternatively, what I tend to do is use an expression on each of the four corners of the power pin telling it to use the corner pin’s data i.e. effect("Corner Pin")("Upper Left")
Then turn off, but don’t delete the corner pin. This way if you have any further tweaks in Mocha, you can just paste the new data onto the Corner Pin and the Power Pin will automatically update.
Hope this helps, mate.
• Archie •