I think Dave's 121GW meter does this with a 3-wire connection.
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The meter you mention looks pretty interesting...I wish it gave selectable watts rather than just VA (since it monitors both I & V in one unit, it should be able to measure watts)..well, it's close! I wonder if there is one that measures output as well, this is for power supply efficiency testing (input & output power)..could use two of these meters, perhaps.
I guess I am not sure what you are after then because some statements don't go together.
The units of V*A is Watts and 1 Volt x 1 Amp == 1Watt so if you don't care about power factor and want to assume a purely resistive load then this meter would do that. The display might have an indicator stating VA or mVA but you can read this as Watts.
The quantity you would be measuring I think is Apparent Power as opposed to Active Power because it is not accounting for phase differences between the waveforms.
It could be helpful if you share with the group what you are trying to achieve - what is the outcome you want. It could be an interesting discussion; I think context always helps when discussing tools.