How to interpret Developer Z-Wave Node columns?

Rx = receive signals.
So homey received that amount of signals from your device, looking at your other devices there is definitely something wrong with your plugs and this happend in a short amount of time, try enabling the log below to see what they send.
If it is COMMAND_CLASS_METER then it is a known issue of the (micro) plugs themselves and you should contact nodon about this, as it is a manufacturing error.
I’ve seen the same with 1 of my micro plugs I have (I have 7 in total).

Tx = transmit signals (send toward the device),
60 times something was send, with 7 (12%) where it was not received by the device (homey knows this by not receiving the “ok I received your command” back, also known as noAck (no acknowledgement))

every mains powered device has a table inside with which devices are nearby (routing purposes).
With heal you let that device know to renew that table.

Send basic on/off, send the most basic on/off signal there is in zwave, every device that can turn off or on should react to this (unless secure, then it depends on what the manufacturer implemented)

Send test frame, sends homey’s NIF (node information frame) to the device, 99% of the time it does nothing, so not useful unless you dive deep into zwave to know what it does.