In my opinion from strongest to weakest:
1. Sophie Turner - really strong, others have no chance against her
2. Emma Stone - fairly strong, solid on No 2
3. Natalie Portman - far away from Stone
4. Anna Popplewell - slightly weaker than Natalie
5. Victoria Justice - much weaker than Anna
6. Sarah Hyland - couldn't punch her way out of paper bag
Basically Sophie and Emma are stronger than your average woman, Natalie and Anna are about average and Victoria and Sarah are jobbers.