I've seen time and time again UK players take a leap when going to the NBA. "why didn't they do that here" is a common misconception.Take Jaden Ivey. All day. Absolutely swap the 4/5 picks. Ivey has the ceiling of someone worth taking with the 1st overall pick.
I don't think Detroit would need to make the trade beforehand, however. There's a chance Sacramento takes someone else.
I feel like Ivey will be one of those players that's a) will take that leap with further development and b) the NBA game will just suit him better.