api-data-owner.js

const data = {};
const getDataGlobal = name => {
  const item = data[name];
  return item && item.value;
}
const setDataGlobal = (owner, name, value) => {
  const previous = data[name];

  if (!previous || previous.owner === owner) {
    data[name] = {
      owner,
      name,
      value,
    };

    window.dispatchEvent(new CustomEvent('changed-data', {
      detail: {
        name,
        previous: previous && previous.value,
        current: value,
      },
    }));
  }
};

microfrontends.forEach(mife => {
  const api = {
    getData: getDataGlobal,
    setData(name, value) {
      setDataGlobal(mife.name, name, value);
    },
  };

  const script = document.createElement('script');
  script.src = mife.url;
  script.onload = () => {
    script.setup(api);
  };
  document.body.appendChild(script);
});