Complex sentence: The twins are a professional wrestling tag team under the ring names Brie Bella and Nikki Bella respectively, collectively referred to as the Bella Twins and they are currently signed with WWE, where Nikki is the reigning two-time WWE Divas Champion.
Split into simpler sentences: The twins are a professional wrestling tag team under the ring names Brie Bella and Nikki Bella respectively, collectively referred to as the Bella Twins. They work for WWE, where Nikki is the reigning two-time WWE Divas Champion.