Answer a question

I was able to change the "Select option" to "Select Location" text in Woo-commerce variable

But I have more than 1 variable with different text. How do I implement this?

add_filter('woocommerce_dropdown_variation_attribute_options_args', 'custom_woocommerce_product_add_to_cart_text', 10, 1);
function custom_woocommerce_product_add_to_cart_text($args){
    $args['show_option_none'] = __( 'Select Location', 'woocommerce' ); 
    return $args;
}

Variations

From: Select Color

To: Select Size

Time: Select Length

Answers

You can check for the attribute, and change the text accordingly

function custom_woocommerce_product_add_to_cart_text ($args) {
    // Args attribute
    $attribute = $args['attribute'];

    if ( $attribute == 'From' ) {
        $args['show_option_none'] = __( 'Select Color', 'woocommerce' );     
    } elseif ( $attribute == 'To' ) {
        $args['show_option_none'] = __( 'Select Size', 'woocommerce' );         
    } elseif ( $attribute == 'Time' ) {
        $args['show_option_none'] = __( 'Select length', 'woocommerce' );         
    } else {
        $args['show_option_none'] = __( 'Default', 'woocommerce' );         
    }

    return $args;
}
add_filter('woocommerce_dropdown_variation_attribute_options_args', 'custom_woocommerce_product_add_to_cart_text', 10, 1 );