I'm facing the same problem and this could be a solution:

editorProps: {
  transformPastedHTML(html) {
    function removeInlineStyles(html) {
      const div = document.createElement('div');

      div.innerHTML = html;
      // remove style property from each element (or of any kind you need)
      div.querySelectorAll('[style]').forEach((el) => el.removeAttribute('style'));

      return div.innerHTML;
    }

    return removeInlineStyles(html);
  },
},