Raj is a substandard network. Not suits for a company like SPNI. When Star did acquisitions from South it got the top players as well as yielding brands in the respective markets. Now there is few choices. ETV from Telugu, Flowers/Mazhavil from Malayalam are the only good channels Sony can go for. Sun may not willing to sell their buisness to anyone as of now. Likewise ETV owners wish to stay their homeland, same with Manorama. When it comes to Flowers, one of the reason to start the channel is to showcase a regional alternative against corporate takeovers (When Star bought Asianet). So its difficult for Sony to expand through aquisitions. When one do aquisitions it should be beneficial for the buyer atleast at a small margin. Don't think channels like Raj, Polimer, Kasturi, Amrita etc can serve that. Instead its better to start new channels.
But if Jio Star takes favorable decision, Sony can buy assets(current serials, show rights for a certain period)of replicated channels of JioStar. Example Colors Tamil, Colors Marathi etc and rebrand it to Sony.