According to Jim Bowden of The Athletic, the Red Sox have engaged in trade talks centered around Andrew Benintendi. Bowden further reported that the Red Sox are looking for a pitching and outfield prospects.
This is a package that the St Louis Cardinals could put together as the organization has plenty of young outfielders and young pitchers. The headliner of such a package would probably be Tyler O’Neill, but if the Cardinals wanted to hold on to him then they could perhaps include Lane Thomas or Justin Williams and a better pitching prospect.
Of the pitching prospects, the Cardinals may be willing to include someone like Austin Gomber, Jake Woodford, Daniel Ponce de Leon (who is probably too old for the Red Sox), or maybe even Johan Oviedo.