I said Marte has never played RF in his career, he hasn't. (Heyward has never played LF in his career FYI) The Royals once upon a time tried Alex Gordon in RF because of his athleticism.. he wasn't that good out there so they left him in LF instead and he's been one of the best defensive LFs in the game for about a decade.
If we wanted to go get a good defensive LF with a good arm who is right handed with power, why not just go after Ozuna who is a free agent without giving up assets?