const imgArrs = [‘imageurl1‘, ‘imageurl2‘, ‘imageurl3‘]
const loadImg = () => {
    if (!imgArrs.length)  return;
    const img = new Image()
    img.src = imgArrs[0]
    img.onload = () => {
        setTimeout(() => {
            document.body.appendChild(this)
            imgArrs.shift()
            loadImg()
        }, 2000)
    }
}
loadImg()