its difficult to say, no one really knows for sure. She has a magic compass given to her by her grandma and she swears it has something to do with her being related some way or another to being the hero of hyrule, so my theories are this:1: Shes a literal descendant from one of the Links from the timeline. (Link doesn't get reborn into the same family bloodline it seems so if he ever made babies there could be "hero descendants" everywhere lol)2: She COULD be the current Link's long lost sister/cousin or sumthn and no one knew3: She could be one of Zelda's descendants or family in the same manner4: She could be a "Back up" hero, in case link fails. For the zelda lore, in OoT, there are 3 different timelines that can happen depending on if link wins, fails, or cannot beat ganon in time: so its possible Linkle exists as someone who can possibly wield the triforce of courage if Link dies or fails or whatnot5: She could honestly just be some poor confused girl with the love of being a hero and the skill to get it done and have no relation to any Link or Zelda at all and her name, clothing choice, physical features etc. are all just coincidence >u