Tell us about yourself!
Saying that this is made from an old psu is like saying you made a car from a spare tire... you used 2 commonly available parts from a psu and purchased a whole lot more & a custom pcb. Granted you could mention that in your parts list that these could be obtained from an old psu but the title to me implies that by reconfiguring and adding only a few parts to an old psu you made an inverter.
In australia most newer houses have ecd (earth current detector) that shuts off a safety breaker if there is ANY leak to ground and it does it fast enough to not kill the human that completes the circuit. I would assume this isolation would rwnder the ecd useless making this device less safe in aus.