Southern Railway will never introduce any train themselves, They are lazy AF. TVC div and MAS div is good in giving up their train to other zone but wont be energetic enough to take.
Also "Rake transfer" or "running for 3 decades" has nothing to do with zone change. It is going to be prestigious no matter what. MAS SBC mail used to be SR train before they gave it to SWR bangalore. So shifting zone for decade ran trains always happens.