Where do you get those video previews? I mean those you post under the links.
Just copy URL of video thumb on xhamster by right-clicking on it. Or if you don't have it in opened menu - then you need to open source code of the page and find there following code with url you need, for example:
<a class="video-thumb__image-container thumb-image-container" href="https://xhamster.com/videos/english-milf-eating-out-lesbian-beauty-9724883" data-sprite="https://thumb-v3.xhcdn.com/a/ZzkZZ2B5Fm7YbJRx2YgHAQ/009/724/883/240x135.s.jpg" data-previewvideo="https://thumb-v3.xhcdn.com/a/vA3hpqQMbOMuhJ2OOlrYRA/009/724/883/240x135.t.mp4">
<i class="thumb-image-container__icon thumb-image-container__icon--hd"></i>
<img class="thumb-image-container__image" src="https://thumb-v-cl2.xhcdn.com/a/42kYgqL8eWDHKZ1-UYG8OA/009/724/883/240x135.2.jpg" onerror="window.Thumb && window.Thumb.onerror(this)" alt="English milf eating out lesbian beauty ">
<div class="thumb-image-container__duration">09:55</div>
</a>
You need this part:
data-previewvideo="https://thumb-v3.xhcdn.com/a/vA3hpqQMbOMuhJ2OOlrYRA/009/724/883/240x135.t.mp4">
Just copy this inner URL and you will get the video preview.