Woocommerce only show sales icon on variation thats on sale

I have a product in woocommerce let’s say a sofa, it has three color variations. Red, green, blue.

Now I want to put the red sofa on sale, I add a SALE price and now <span class=”onsale”>Sale<span> tag is applyed on all variations on my product.

Is there a way to filter so that it only appears on the variation which is on sale and is removed on the others?

Something like, if onsales price is true output <span class ="onsale">Sale<span> if empty display none..

Thanks