Thanks! However, if you print the keys in m.state_dict(), you will find:
['embedding.weight',
 'net_a.embedding.weight',
 'net_a.fc.weight',
 'net_a.fc.bias',
 'net_b.embedding.weight',
 'net_b.fc.weight',
 'net_b.fc.bias']

Are all the embedding weights above tied?