SOLVED. YA or MG SciFi/ Fantasy book about a boy who is transported to a steampunk world and ends up taken in by the queen/ leader, but loses his hand in the end. [s]

[CIENNA]

A book where a boy is transported into a steampunk world. I THINK the boy's original home(before he's transported to the normal world) is like Victorian London or somewhere in the UK, but I don't know, so take that detail very lightly.
I don't remember if he's trying to get back home or anything, but he meets a robot girl who was made to have a 'real' heart, and was made for the queen so she could have a real child or something.
basically all of the people in the city/kingdom are like robots or cyborgs, like they all have some sort of modified aspect to them.
Eventually the boy is adopted by the queen of the steampunk city/kingdom because the queen wants a real human child. I forget if it's revealed that the boy was transported specifically so he could be adopted by the queen, or if it was a coincidence and the queen only found out about him afterwards and decided she wanted him.
Sometime after he's taken in by the queen, they go on a ride in like a blimp or hot air balloon or something, and I think the queen tells the boy more about the kingdom or the lands while they're riding.
Sometime after they get back from the trip, he opens a gift someone delivered for him which I think ends up being a trap. He loses his hand, which ends up getting replaced with a prosthetic one. Because he's not fully human anymore, the queen doesn't want him and is upset I think, and I think she either just sends him away, or she has him brought back home.
At the end the boy ends up returning to his normal world, and goes home with the prosthetic hand. I think the robot girl he met before is introduced to the queen, too? But I don't know if the queen accepts her or not.
I read it sometime during or before 2017 I believe. I'm unsure when exactly I read it, but it was before high school, which was before I turned 13. I was 12 in 2017. The range would probably be from 2013-2017.

[Angela]

Flights and Chimes and Mysterious Times by Emma Trevayne?

[CIENNA]

Angela wrote: " Flights and Chimes and Mysterious Times by Emma Trevayne?"

YES!!! I think that's the one!! Thank you!!