Franson would be a good fit, and there does exist some needs for the two teams that could generate a trade. Buffalo could use some more cap space, and Franson's a fairly redundant piece behind Risto and Bogo; Edmonton on the other hand needs a RH pp defenceman that can at least share duties with Larsson.
Also I don't think Franson (while not great) is the tire fire defensively that Wisniewski or (especially) Wideman are, so that's a plus. (Though he's not as good offencively, but at the same time I think the team is going to want to push Larsson into those roles)
I'd offer up up Fernece's insurance papers, but I suppose I'd do a 3rd.
Klefbom-Larsson
Sekera-Fayne
Davidson-Franson
to start the season, I could get behind that... Though I wouldn't be surprised to see that grow into...
Klefbom-Larsson
Davidson-Sekera
Nurse-Franson
... by midseason. Davidson's a more rounded (and likely better) partner for Sekera; and Nurse covers for Franson's mobility issues. Fayne becomes a nice injury insurance policy.