During the wedding in Potsdam, Princess Sophie wore a diadem from her ancestral House (Isenburg-Büdingen). After the wedding the Princess swapped for a diadem of her new House (Prussia).
I liked that, it was sort of a symbolic goodbye to her old House and welcoming her new House.
This scenario would mean: in the morning the bride wears a diadem from the Maison de Lannoy. In the evening the bride wears a diadem from the Maison de Nassau.