Corner Pin Offset allows you to track four points and then use an offset before creating a Corner Pin.
I did this tool while working on Wonder Woman 1984 to help the team with a sequence where we had a lot of photos to add on different frames around an apartment. Sometimes we had other objects in front of one of the corners of the photo frame, and with this tool, we could track another point and then offset it to where the corner was.
You need to use a Tracker node first, and when you have it you select it and link the points to CornerPinOffset. As you can see in the image, you can do all the points at once (1 is lower left, 2 is lower right, 3 is upper right, and 4 is upper left), or do them one by one in whatever order you want. You have the To and From values the same way you have them in a CornerPin, and at the bottom of the properties you have the offset values you want to apply to the tracker.
Expand CornerPinOffset