JSFiddle - React, Tailwind, and code Playground

HTML

<div class="post">
  <div class="texto">Bla bla bla</div>
  <div class="thumb"><img src="/img/logo.png" alt=""></div>
  <div class="imagem"><img src="/img/logo.png" alt=""></div>
</div>

CSS

.post {
  position: relative;
  height: 100px;
  width: 100px;
  border: 1px solid red;
}

.imagem {
  opacity: 0;
  transition: opacity .8s;
}

.post > * {
  position: absolute;
  left: 0px;
}

.thumb {
  bottom: 10px !important;
}

.thumb img {
  height: 10px;
}

.thumb:hover + div.imagem {
 opacity: 1;
}