I would strongly suggest you take a road trip to a recumbent specialty store. A typical bike shop that stocks a couple of recumbents isn't good enough. There are several quite different recumbent bike/trike designs and they all ride a little differently. Under seat steering, common on tadpole design trikes, won't put very much stress on your repaired shoulder, but might not provide enough elbow support to be comfortable.

There are also storage and transportation issues with recumbents that are a little different than conventional bicycles. A recumbent specialty store will have solutions to offer you.

Be prepared that once you get acclimated to riding a recumbent you might not want to go back.