Wanting to confirm, the Luxpower SNA5000WPV output volage per the data sheet is 230/240V. So when paralleling these units in 3 phase that will only give 230/240V per phase (to neutral)? Does that mean it will give 380/400V between phases?

Yes, 230 V line-to-neutral/phase voltage (the per phase voltage) adds up to 400 V line-to-line voltage. (Remember that the three phase voltages are 120 degrees out of phase, so if you then measure between two phase terminals, let's say Vab, then you will get 400 V.