Leonora Elizabeth is a very beautiful name, elegant yet classic. It is one of my favourite combos of yours, Lotte. 
Here are two ideas as I stated:
Elaine Betsabea 
Elaine has a similar root and meaning to Leonora.
Betsabea is also of Hebrew origin like Elizabeth and has a similar meaning.
Leontine Nuo 
Leontine has a similar sound to Leonora and a similar vibe.
Nuo in Chinese means promise - Elizabeth means God is my Oath.
Bonus because I felt it: Eudora Promise 
Eudora means generous (One of the possible meanings of Leonora.)
Promise - from God is my Oath.
I hope you like it! As for non mandatory rule (IDK, almost became a tradition of this thread), feel free to rename anything from my lists or lists of others!