Turning off the wi-fi is a duff idea, it means the two 0lder boys in the house dip out because of the 9-year old's behaviour. Why should they be punished?
School nights - fed by 1800, one hour of screen time, bed by 2000, lights out 2030 (latest)
Judo, keep it up but make sure it's a class where they do lots of pyshical exercise too, not just kata, she'll be knackered.
If she steps out of line, take away her phone. If she has a tantrum, throw it down the loo.
Try asking your husband what sort of a man he is; 'Did I marry a man or a mouse, or is easily dictated to by a 9-year old girl?' That sort of remark tends to cut more deeply than wishy-washy liberal 'parenting counselling' (what the hell is parenting, is it a word?)
Definitely cut out the take-aways; they'll be full of the sort of salt, sugar, additives and E numbers that lie behind ADHD and sugar-rush hyper-activity. Such junk should be the off treat, not a main meal at nigh on midnight.
And did I suggest asking your husband what sort of a man he is? You've got 5 kids, I'm sure you don't want them to grow up in a broken home?