wtf imports

import-stuff.js

// A, B, G are undefined when trying to reference them
import { A, B, G } from 'module-b';

// A, B, G are defined properly
import * as Stuff from 'module-b';
const { A, B, G } = Stuff;

module-a.js

// module-a/index.js
import A from './a';
import B from './b';
import C from './c';
import D from './d';
import E from './e';
import F from './e';


export {
	A,
	B,
	C,
	D,
	E,
	F
};

module-b.js

// module-b/index.js
import * as Things from 'module-a';
import G from './g';

const stuff = {
	...Things,
	G
};

export default stuff;

Are A, B, C, etc defined as of line 10 in module-a.js? Like, if you toss a console.log there, would it log something or undefined?

Another thing to try:

// in module-a.js, replacing lines 10-17
export {
  A as A,
  B as B,
  C as C,
  D as D,
  E as E,
  F as F
};