Webpack would be the only way I know of to do this (basically concatenating all the scripts together). Note they do have some available libraries built in, including fetch:
// From fetch
fetch,
Request,
Response,
Headers,
// URL Standards
URL,
URLSearchParams,
// bas64
atob,
btoa,
// Crypto
crypto: new Crypto(),
TextDecoder,
TextEncoder,
// Debugging
console,
// Async
setTimeout,
setInterval,
clearTimeout,
clearInterval,
...
As far as issues with webpack, I have not had any - though as you say it may be package dependent.