That's a question for theologians. At least when it comes to IVF kids, all Christian denominations, AFAIK, believe they have a soul like anyone else. I would be surprised if they did not come to the same conclusion for kids like this. If they didn't, they would be punishing the child for the actions of its parents.
The Catholic Church has said that despite the fact that it considers IVF a sin, the child created by IVF is blameless for such sin.
IVF "ingredients" aren't created out of thin air. They're real sperm and real eggs. That's why the Church still recognizes the presence of a soul. Actual conception takes place, but not in the way intended by God (which is why it's forbidden to Catholics).
If I can take a pile of dung and use it to engineer sperm, it's not conception. Therefore, there is no soul.