OK Matt, no solar, so that rules out a difference between import and net. That’s progress.
Swapping the two lower pf CTs doesn’t really help, so nothing there.
The new information is that in addition to the Wh being about half, individual appliances are coming in at about half. Now I see two possibilities:
First, the CTs may be defective. Very unlikely.
Second, the phase assignments are wrong. More likely, and a typical symptom of this is readings that are half what is expected. I recently published a newer instruction for assigning the mains phases. Can try going through the procedure to validate your phase assignments? Then, if anything changes, retry those appliances and see if it reads more in line with the nameplate?