Hello,
I have checked the image it is Awesome icon and we can add it as it is.
Please add this code to the Theme Settings > Custom CSS > Global:
body .wd-add-btn-replace .add-to-cart-loop::before {
content: "\f05a";
font-weight: 900;
font-family: "Font Awesome 5 Free";
}
Please make sure the Font Awesome icons have been enabled on your site. You can enable it in the Theme Settings > Performance > Font icons > set “Always use”.
Best Regards