If you are set on having the root hierarchy be different you won't be able to use a schema, but you could either use the

Dendron: Apply Template

command (easy, but manual) for those notes, or use notetraits (hard, maybe still have to apply the trait manually anyway, I've never used them so note sure https://wiki.dendron.so/notes/bdZhT3nF8Yz3WDzKp7hqh/#summary)