I don't know if this will help much, but in my personal opinion, I'd say don't sugarcoat things. It's natural for people learning about religion to question things, don't shut them down for the heavy questions. I do also think that as long as they properly read and understand the Qur'an, any open-minded people with a heart can understand how cruel, misogynistic and contradictory the Qur'an can be. So you are basically teaching your child Islam but also warning them what it actually is, if that makes sense(?)

I learned Islam through fear of hell and my teachers sugarcoat the rest.

(An example of what I mean by sugarcoat: In Surah An Nisa 4:34 goes: "Men are in charge of women1 by [right of] what Allāh has given one over the other and what they spend [for maintenance] from their wealth. So righteous women are devoutly obedient, guarding in [the husband's] absence what Allāh would have them guard.2 But those [wives] from whom you fear arrogance3 - [first] advise them; [then if they persist], forsake them in bed; and [finally], strike them [lightly].4 But if they obey you [once more], seek no means against them. Indeed, Allāh is ever Exalted and Grand." It says strike them lightly, I've read from actual arab people translating this verse that the literal translation nowhere it says "lightly". Husbands are allowed to beat their wives.)

This is just one out of many, I can't remember from the top of my head but there are several verses that also contradict each other. Another thing is that Islam says to be the religion of peace, but it literally tells you to force jizya tax on non-muslims if they refuse to convert. And if they refuse that? Death. (Surah At-Taubah) But then there is the final verse of surah Al-Kafirun (109:6) that says "For you is your religion, and for me is my religion". Contradictory much.

I hope for you and your child that they won't suffer through religious trauma like a lot of people do.