What's the difference between this packages? are all doing the same ?
Using brunch here, but not brunch specific question.
http://libraries.io/npm/6to5-brunch
Well for one thing, 6to5 was renamed to Babel. This is why you see 6to5-brunch releases stop at 3.0.0, and babel-brunch releases start at 4.0.0.
ES6 module transpiler (initially curated by Square) development seemed to slow down quite a while ago. The project began migrating developers from esnext development to 6to5 development, effectively joining forces with 6to5. (This was obviously before 6to5 was renamed to Babel) This is likely why you will the es6-module-transpiler-brunch module is very out of date and no longer actively developed.