Optimize Switch MOSFET AC
If you have two indipendent power busses you need 4 bilateral switches.
Eeach switch needs either two MOSFETs or (highiy deprecated due much higher losses) one MOSFET and a bridge rectifier.
In both cases you also need four indipendente floating gate drivers.



simulate this circuit &ndash; Schematic created using CircuitLab
So it all just sums up to 8 MOSFETs. This can be trimmed down only in case you reduce your specifications allowing, for instance, a single shared neutral connection which doesn't need to be switched.
In any case I hope you've taken care of switching transients, abruptly switching inductive currents would otherwise lead to pyrothecnic effects.
Also consider that 600 V BVds MOSFETs are way from enough.
Your two busses are 230 V nominal RMS voltage, this means 325 V peak  and if they happen to be out of phase by 180° each switch may see up to 650 V. Add some 150% margin and you get to the 900 V or 950 V class devices.
Edit:
I join the other members opinion in comments, you seem to overlook basic safety, regulatory and operational requirements.
I strongly discourage you to keep on trying. This is probably illegal but surely very dangerous. That's a job for professional power engineers.