If you want to show stars instead of theme ratings in Woocommerce, you can do this by changing the Woocommerce star ratings.

The Stars rating is the default rating system in WooCommerce, so to match the rating system with themes we have to disable this default rating first then replace this with the WooCommerce default. you can get it from plugins/WooCommerce/assets/images directly and place it in your themes images folder star.

Now add the below code to your custom.css (if you have style.css as a child theme):

.star-rating{float:right;width:85px;height:20px;background:url(images/star.png) repeat-x left 0} 
.star-rating span{background:url(images/star.png) repeat-x left -35px;height:0;padding-top:20px;overflow:hidden;float:left} 
.hreview-aggregate .star-rating{margin:15px 0 0 0} 
#review_form #respond{position:static;margin:0;width:auto;padding:0 0 0;background:transparent none;border:0} 
#review_form #respond:after{content:"";display:block;clear:both} 
#review_form #respond p{margin:0 0 15px} 
#review_form #respond .form-submit input{left:auto} 
#review_form #respond textarea{-webkit-box-sizing:border-box;-moz-box-sizing:border-box;box-sizing:border-box;width:100%} 
p.stars:after{content:"";display:block;clear:both} 
p.stars span{width:85px;height:20px;position:relative;float:left;background:url(images/star.png) repeat-x left 0} 
p.stars span a{float:left;position:absolute;left:0;top:0;width:20px;height:0;padding-top:20px;overflow:hidden} 
p.stars span a:hover,p.stars span a:focus{background:url(images/star.png) repeat-x left -20px} 
p.stars span a.active{background:url(images/star.png) repeat-x left -35px} 
p.stars span a.star-1{width:20px;z-index:10} 
p.stars span a.star-2{width:35px;z-index:9} 
p.stars span a.star-3{width:50px;z-index:8} 
p.stars span a.star-4{width:65px;z-index:7} 
p.stars span a.star-5{width:85px;z-index:6}

Also add the below css, if there are duplicate stars on your product:

.star-rating span:before, ul.products li.product .product-details .star-rating:before {
content:none; 
}