I have never seen rankings like you would want. And, even if they existed, its what the individual teachers do that is important. There is nothing better then "boots on the ground". Once you figure out where you want to relocate - then start visiting the schools. Its really the only way to know what your child can expect.
And when you do start visiting the schools, here is a good link giving you ideas on what to look for.... https://www.additudemag.com/changing-schools-adhd-child-making-choice-finding-school/?utm_source=eletter&utm_medium=email&utm_campaign=school_october_2017&utm_content=102517&utm_source=ADDitude+Master+List&utm_campaign=dfd75c6565-EMAIL_CAMPAIGN_2017_10_24&utm_medium=email&utm_term=0_d9446392d6-dfd75c6565-288295765&mc_cid=dfd75c6565&mc_eid=34d357d554