Will the wife be sinful and held accountable by Allah if her husband spends on her from borrowed money, and he does not return these loans to their people?

You bear no sin for benefiting from money your husband borrowed and handed over to you for maintenance. The sin falls upon him if he does not return those funds to their owners. You should advise your husband to be cautious about borrowing without need and to be diligent in repaying debts without procrastination.