The slider used on index.html is slick slider and the images and text can be edited in the following markup

 <!--start slider -->
 <div class="home-slider">
  <div class="media-container media-container--slider" style="background-image:url(images/store_slider.jpg)">
    <div class="container-custom custom-height-container flex">
     <div class="slide-content flex-center ">
      <div class="title-block ">
        <h1 class="title-block__title--slider"><span>Sell your products</span></h1>
        <h3 class="title-block__subtitle--slider">The simplest way possible</h3>
      </div>
      <a href="cart.html" class="btn btn--black btn--60">Add to cart</a>
     </div>
  </div>
 </div>

..

</div>

The class that triggers the slider is .home-slider

The glitch effect comes from https://tympanus.net/Tutorials/CSSGlitchEffect/index3.html 

It is not available on Internet Explorer.

the code related is found on index.html and app\css\scss\elements\_homeslide.scss

The css for this slider is found at app\css\scss\elements\_homeslide.scss

The class that triggers the slider on the product page is .product-gallery

The slider used on the shop page is swiper slider and the images and text can be edited in the following markup

<!-- big images -->
 <div class="Gallery swiper--container">
  <div class="swiper-wrapper">
  <!--slide 1-->
   <div class="swiper-slide" style="background-image:url(images/store-product-list_clean_03.jpg);">
    <div class="slider-content">
     <div class="title-block ">
      <h1 class="title-block__title--swiperBig"><span>50% Sale</span></h1>
      <h3 class="title-block__subtitle--swiperBig"><span>On all orders above $100 + free shipping</span></h3>
     </div>
     <a href="cart.html" class="btn btn--black btn--60">Read more</a>
    </div>
   </div>
 <!--slide 2-->
...
 <!-- thumbs -->
 <div class="Thumbs swiper--container">
   <div class="swiper-wrapper">
    <!--slide thumb 1-->
    <div class="thumbs swiper-slide">
    <div class="thumbs title-block ">
     <h1 class="title-block__title--swiper">Accesories</h1>
     <h3 class="title-block__subtitle--swiper">Refine your selection</h3>
    </div>
    <img src="images/store-product-list_clean_05.jpg" alt title="shop">
   </div>
 <!--slide thumb 2-->
...
 </div> <!--end wrapper-->
</div> <!--end container-->

the css can be modified at app\css\scss\elements\_shop.scss