I think
Annabella is lovely and while it is very frilly and feminine, it's also strong too. I don't think it's over the top frilly though. It may get a little more popular because of
Isabella, but they are different sounding names, so it may not have the same appeal.
Bella is a very sweet nn. You might get people trying to shorten it to
Anna, but if you don't want that, then just let them know.
Annabella Catherine, while a very long combo, is also very pretty.