Does it harm for a menstruating wife to shorten her husband's hair to exit the state of Ihram after performing the rituals of 'Umrah?

There is no harm in a menstruating wife shortening her husband's hair when he exits the state of ihram after performing 'Umrah. This is because a menstruating woman is like others in all actions and rulings, except for what has been explicitly excluded. It has been authentically narrated from 'Aishah (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) said to her when she menstruated: "Perform all the rituals of Hajj that a pilgrim performs, except for circumambulating the Ka'bah."

The fact that the wife is still in a state of ihram does not affect the ruling, as the majority of scholars do not consider whether the person cutting the hair is in a state of ihram or not.