Kike Hernández
Kike Hernandez has made a name for himself around the game of baseball for his versatility, logging 1000+ innings at shortstop, second base, and center field while also appearing in left field, right field, third base, and first base defensively.
The Cardinals love versatility, so having someone like Hernandez who will accept his role and play all over the field is a win, but he's also a more natural shortstop than someone like Donovan or Saggese.
A right-handed hitter, Hernandez would also give the Cardinals some more balance off the bench, and he did post a .731 OPS after being traded back to the Dodgers from the Red Sox last season. He's posted multiple big league seasons with an OPS+ above 100 over his 10 years at the highest level, and would certainly be an asset to the club.
It's unclear if the Cardinals will for sure add an outside shortstop to their mix, or even how quickly they'll make that decision. I imagine it'll be a mixture of factors, including the early results they are seeing from a Saggese at shortstop, the progression of Edman, and if some of these shortstops are being taken off the market.
Keep an eye on this storyline, as we may see another veteran position player added to the Cardinals bench in the coming weeks.