It fits, even on tiny commuter jets. We've used ours on Embraers before. I think it should fit in the bulkhead row.
If you can't get a bulkhead row, and if you have two adults in your party, you could have one adult sit in the seat in front of the child, so that you're not inconveniencing a stranger. Otherwise, you could offer a gift card to the inconvenienced stranger. That's what we would do -- although all of our flights at the time were domestic.
If the child pushes with their feet on their seatback it can cause the back of the scenera to touch the seat in front, which could disturb the person sitting in it. So you might want to do what you can to discourage your child from doing it if you can.
They really are great for travel. Have a nice trip!
ETA-
Here's a picture (not a great one... but at least you can see that it fits). This was, I think, an MD80.
ETA2:
Here's a better picture. (found on the googles) And
here's the article related to the picture. Good info!