1) it renders import and from...import statements to equivalent ES6 imports. If you use something like Webpack down the pipeline you can already mix ES6 imports and CommonJS requires. Also, BabelJS by default transpiles ES6 imports to CommonJS requires.

2) What do you mean exactly?

3) There's no direct from-python loader, but the compilation can be splitted in two steps with the BabelJS Webpack loader used for the latter