For the most part I don't engage in "what if" trade talk. No matter that the fans or the media think would be a good idea, for the most part the Cardinal FO doesn't agree so I find it a waste of time.
Case in point is ESPN's David Schoenfield and the suggestion that St Lou trade with Boston.
Boston Red Sox trade RF Mookie Betts and RHP Nathan Eovaldi to the St. Louis Cardinals for IF/OF Tommy Edman, OF Randy Arozarena, 1B/RF Jose Martinez and LHP Brett Cecil.
There is no way the Cardinals would give up those players for a one year rental of Betts. They almost never trade for a 1 year rental player. Yes they traded for Goldschmidt but in reality they gave up 2 minor leaguers and a journeyman pitcher. Plus they were pretty confident they could sign him to an extension.
According to the talk they expect Edman to be a contributor on a regular basis. They will move him around to a number of positions to get him the ABs.
I am ignoring Eovaldi as he might not even make the team. He isn't strong enough to be the #5 SP and he as a reliever, he's got too much competition. His last decent season was 2015 with the Yankees. He is going to get $17 mil a year for the next 3 years. There are a lot of better options out there for that kind of money.
Lastly, just because the BoSox want to dump salary doesn't mean StL wants to be hamstrung with it.