I should think it obvious that God the Father does not have a body and thus has no sex. He is not male or female and has no attributes of male or female bodies. So we must distinguish in this case between biological sex and personal attributes such as masculinity and femininity which could apply even to a spirit being.
What people often mean when they claim that God has both male and female traits is that God exhibits all the good traits which we attribute to both men and women, including some that we might associate more with one gender or the other (such as caring, nurturing, compassion for females or strength and courage for males). This part is true. God does exhibit all good traits.
However, such character traits are not necessarily either masculine or feminine. We often associate certain traits more strongly with masculine or feminine roles, but the traits themselves, in being good and noble, are not solely the province of either gender. A man can be caring or compassionate and do so without being feminine. A woman can be courageous or strong without being masculine. So the roles of masculinity and femininity are not merely a collection of traits.
I would claim that the underlying basis for masculinity and femininity are in their contrast to one another and their emphasis more so than individual traits, and especially their contrast with regard to authority and leadership. The masculine role is one of leadership, authority, protection, and provision with respect to the feminine and the feminine role is one of receptiveness, submission, vulnerability, and willingness to be led with regard to the masculine.
Given these definitions of masculine and feminine, as contrasts to one another rather than a list of traits, it does not make sense to claim that God has both masculine and feminine traits. Traits have no gender. Masculine and feminine refer to roles, not merely a group of traits.
Under this definition, God is only masculine because He holds only the role of authority, provision, protection, and leadership with regard to everything else that exists - His creation. God does not hold the feminine role. Ever. He submits to no one. He is not led by anyone. And thus while we can acknowledge that God can and does exhibit compassion, nurturing, and care for those in need, these do not make God feminine any more than they would make any man feminine. They are noble and good traits and have no inherent gender, even if the female sex is more associated with them, and perhaps exhibits them more often.
God's role with respect to His creation is the role of the masculine, and thus we should only refer to God with masculine pronouns. That is also, not coincidentally, the way that God has revealed Himself to us. It is a serious error to claim God is feminine, and we must be careful to avoid this error.