Hello,

Please make the full backup of your site as well as the Theme settings export and check login/register on the Storefront theme to detect if our theme causes the problem. Storefront is a free theme developed by Woocommerce.

You can configure the swatches as text and then custom with CSS. Let me know if you need help. https://xtemos.com/docs/woodmart/variable-products-swatches/

Best Regards