Rafaela is only now giving her memories, and we really don't know the extent of what this means. It might just be memories, it might be her experiences and fighting instincts (Rafaela being a former #2 and a master of Youki suppression).

Only Irene and Teresa really gave Clare anything. Jean saved her, but that doesn't mean they are connected in any kind of way that is more than a simple delusion inside Clare's head similar to Guts (various), Alita (evil krauser guy, enemies), or Wolverine (Ms. Marvel, other old friends/enemies).

As for the ability, there's nothing particularly "new" about it. It is still the same Flash Sword, Clare has just elevated her ability to control her own Youki in the seven years since she last used the skill. Before she could concentrate a great deal of her power into the arm, now she can move all of it there.