How to restore to backup with new Apple ID/iCloud?

My mother just got her new iPhone SE, and we want to transfer all her stuff from her old iPhone, to her new one. The problem is, we want her to have a new Apple ID/iCloud account for her new phone (there are many reasons why we need a new Apple ID, won't go into why). Once we do that, I also want to change the Apple ID on her iPad. So is there an efficient way to restore to backup with a different Apple ID? I had a plan but don' know if it's good: Backup old phone to iTunes. When setting up the new iPhone, create new Apple ID and restore to backup using iTunes. Is this a viable method? Please let me know. Thanks!