(source: https://jsfiddle.net/bLhzrne5/)

fiddle.css

.some-class {
  background-color: yellow;
}

fiddle.html

<button data-toggle-class="#targetDiv:some-class">Toggle this Class on the Element</button>
<div id="targetDiv">target</div>

fiddle.js

document.querySelectorAll('[data-toggle-class]').forEach((element) => {
  element.addEventListener('click', (event) => {
    event.preventDefault();
    const [target, className] = element.getAttribute('data-toggle-class').split(':');
    document.querySelector(target).classList.toggle(className);
  });
});