It goes one of two ways:
1. Broly kills Moro instantly before he can drain any energy, ending the arc anticlimactically.
2. Moro endures Broly's attacks much like his far weaker self took SSBE Vegeta's kick and lasts until he drains most of Broly's energy. This brings Moro to a level that not even Goku and Vegeta's training will help them against. Beerus would have to get involved and either succeeds by sealing Moro away or is killed as well. In the latter case, Moro goes unchallenged in Universe 7 until whatever point that the Daishinkan decides it's necessary for Zen-Oh to erase Universe 7.