What is wrong with الْمُسَافِرُونَ أَكَلَ الطَّعَامَ as the conversion of أَكَلَ الْمُسَافِرُونَ الطَّعَامَ?

Changing a Verbal Sentence into a Nominal Sentence

• The object should be moved before the mubtada.
• The verb should be passive.
• The noun should be feminine singular.
• The verb should be masculine plural because the mubtada is masculine plural.