Maybe if the Brits were to acquire Ospreys for some other role it would be a possibility but I can’t envision them ever buying the aircraft just for the COD role.
That was my thinking (well I think mine was that in reverse!)
Buy the Long Range version of Osprey (which happens to be the COD platform) to do lots of jobs it just so happens that one of them would be the one it was originally optimised for
“buy an Osprey, get a fleet air arm”