Louisa is a beautiful classic. It makes me think of
Louisa Mae Alcott and "Little Women." It's known, but not overly used. It would age beautifully.
Lovisa is more of a mixed bag for me. The name itself if lovely. It has a more sophisticated air than
Louisa. But the potential nn Lovie is where I get iffy. In theory, I love the idea of nn Lovie, as in Mrs. Thurston
Howell III. But if I ever met a "Lovie" in real life I'd wonder if her parents had really thought that one through. Wheels within wheels, signifying nothing. I made my brain hurt.