User blog comment:FairyRaven/Fairy Tail Chapter 336: In Order to Live Today to the Fullest, Review and Commentary/@comment-7418318-20130621152145/@comment-7418318-20130621173629

F-Lucy, a right-hander, couldn't use her right hand any longer and thus was forced to write with her left (unless she wrote it in her prison cell, before Mercurius collapsed, but that makes it even less likely that she'd have any kind of reliable information).

If I try to write something with my left hand, I can't read it myself.

And Yukino didn't seem to have the slightest bit of difficulty in reading it either.