Square Enix being bought by Sony is already a big "IF". I actually believe there is a possibility some of the rumors originated from Square Enix wanting to sell Crystal Dynamics and Eidos Montreal, and maybe Sony had some interest. However, Embracer Group is the one that got them. Maybe Sony will pick Square Enix up, but I would take it as a grain of salt for now and not read too much into it. One thing that we have seen time and time again in recent years, is that nobody knows anything when it comes to acquisitions.
However, hypothetically if the two were to join forces, I wouldnt rule it out completely, but I think the more likely candidate would be to remake Legends of Dragoon from an already Sony owned studio being Bluepoint.