In 1989 or thereabouts? Tough question, mostly because Sony wouldn’t. Paramount Communications is rich and powerful having just sold off the rest of Gulf+Western and CEO Martin Davis (edit: Marvin Davis bought Fox lol) is already planning to merge with Viacom. If Sony gets in it’ll have to be hostile with Viacom as the white knight saviour
Taking Columbia off Coca-Cola’s hands was a fairly cheap $3.4 billion and very friendly—MCA’s price was nearly double ($6.5 billion) a year later, and Paramount’s eventual price higher yet ($9.75 billion) in 1994 after a bidding war. Does Sony really want to pay $6-9 billion dollars in a hostile takeover attempt considering MGM/UA was only a lousy $1.45 billion two weeks earlier? They do not.
If you want Sony to buy Paramount around 1989 instead of Columbia you need a POD further back to make either the price much lower than OTL or Sony quite a bit bigger. Perhaps Paramount Pictures has Columbia level success in the 1980s under different management? But of course *Paramount will little resemble the OTL ‘89 Paramount you’re curious about coming under Sony’s control.