Using mix-blend-mode: Difference works well when the background color is black to change the text color to white. Move the mouse over the text to see the effect:

const blackBox = document.querySelector(".black-box");
window.addEventLis tener('mousemove', function(event) {
  blackBox.style.left = `${event.pageX - 50}px`;
  blackBox.style.top = `${event.pageY - 50}px`;
});

.wrapper {
  background-color: white;
}
h1 {
  position: relative;
  z-index: 2;
  color: white;
  mix-blend-mode: difference;
}

.black-box {
  width: 100px;
  height: 100px;
  position: absolute;
  z-index: 1;
  background-color: black;
}

<div class="wrapper">
  <h1>Lorem Ipsum</h1>
</div>
<div class="black-box"></div>

This will not produce white text if the background is not black, which is understandable:

const box = document.querySelector(".box");
window.addEventList ener('mousemove', function(event) {
  box.style.left = `${event.pageX - 50}px`;
  box.style.top = `${event.pageY - 50}px`;
});

.wrapper {
  background-color: white;
}
h1 {
  position: relative;
  z-index: 2;
  color: white;
  mix-blend-mode: difference;
}

.box {
  width: 100px;
  height: 100px;
  position: absolute;
  z-index: 1;
  background-image: url("https://placekitten.com/100/100")
}

<div class="wrapper">
  <h1>Lorem Ipsum</h1>
</div>
<div class="box"></div>

Is there any way to change the text color from black to white when the background is different from white?