w3c-xmlserializer
An XML serializer that follows the W3C specification.
This module is mostly used as an internal part of jsdom. However, you can use it independently with some care. That isn't very well-documented yet, but hopefully the below sample can give you an idea.
Basic usage
const { XMLSerializer } = require("w3c-xmlserializer");
const { JSDOM } = require("jsdom");
const { document } = new JSDOM().window;
const XMLSerializer = XMLSerializer.interface;
const serializer = new XMLSerializer();
const doc = document.createElement("akomaNtoso");
console.log(serializer.serializeToString(doc));
// => '<akomantoso xmlns="http://www.w3.org/1999/xhtml"></akomantoso>'