?php
add_filter( 'http_request_args', function( $args, $url ) {
    // Only affect HTTPS requests
    if ( 0 === strpos( $url, 'https://' ) ) {
        $args['sslversion'] = CURL_SSLVERSION_TLSv1_2; // or TLSv1_3 if supported
    }
    return $args;
}, 10, 2 );

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="https://imaginationcreates.com/wp-sitemap-index.xsl" ?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"><sitemap><loc>https://imaginationcreates.com/wp-sitemap-posts-post-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-posts-page-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-posts-jetpack-portfolio-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-posts-featured-content-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-taxonomies-category-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-taxonomies-post_tag-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-taxonomies-post_format-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-taxonomies-jetpack-portfolio-type-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-taxonomies-featured-content-type-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-taxonomies-featured-content-tag-1.xml</loc></sitemap><sitemap><loc>https://imaginationcreates.com/wp-sitemap-users-1.xml</loc></sitemap></sitemapindex>