E. Marten

You need to use WordPress SEO by Yoast (Props to him!)
Adds “More Sitemaps” to your WordPress SEO Settings. If you are using a second WordPress-Installation in a subdirectory, you can now easily add the second Sitemap into the main one.
If you are using a second WordPress-installation in a subdirectory and want it to be fully integrated it into your main site to prevend struggeling with two or more Sitemaps in your Webmastertools, 
you can easily integrate more sitemaps into your main one. (sitemap_index.xml) 
The Plugin adds your second and third (aso) sitemap into the main sitemap and tooks care about the modification date automatically!
Thanks to Joost de Valk!

IsSiY (Include second Sitemap into Yoast) WordPress SEO Extension

Adds "More Sitemaps" to your Wordpress SEO Settings. Include differen sitemaps to your sitemap_index.xml

SMiLE

SMiLE Basic Web is a powerful, modular, and user-friendly WordPress plugin that integrates multiple essential tools into a single solution. It includes a flexible Contact Form system with real-time email preview via the Customizer, a dynamic Sitemap Generator supporting various formats, and a comprehensive Cookie Consent Manager fully compliant with international data protection regulations such as GDPR and ePrivacy. With lightweight, accessible, and brand-adaptable interfaces, SMiLE Basic Web empowers site owners to ensure transparency, control, and legal compliance while maintaining a seamless user experience.
Key Features:
<ul>
<li>Customizable contact form with advanced SMTP configuration.</li>
<li>Support for multiple custom fields, including new types: single/multi-select, user email, and textarea.</li>
<li>Required field indicators and placeholders.</li>
<li>Field reordering with drag-and-drop interface.</li>
<li>Google reCAPTCHA v3 integration for spam protection.</li>
<li>Send a copy of the form to the user, with a customizable message.</li>
<li>Insert logo and company link in user copy emails.</li>
<li>Privacy policy and legal notice checkbox fields with linked pages.</li>
<li>Optional marketing opt-in field with customizable text.</li>
<li>Explanation field to describe the purpose of the form.</li>
<li>Real-time preview of the user email using the WordPress Customizer.</li>
<li>Optional SEO metadata editor for posts and pages (title, description, and indexation).</li>
<li>Modular tab interface supporting additional tools.</li>
<li>Dynamic generation of:
<ul>
<li><code>llms.txt</code> (text or JSON format).</li>
<li><code>sitemap.xml</code></li>
<li><code>sitemap-images.xml</code></li>
<li><code>robots.txt</code></li>
</ul>
</li>
<li>New “General” tab that centralises global options.</li>
<li>Toggle to allow safe SVG / SVGZ uploads (sanitised & thumb-ready).</li>
<li>Automatic image Alt-Text: copies IPTC/XMP “Alt Text Accessibility” (fallback to Title). 
-Cookie Consent Panel:
<ul>
<li>Clean, responsive, and customizable cookie banner.</li>
<li>Three display sizes: Small, Large, or Fullscreen.</li>
<li>Consent tab with position options: Left, Center, or Right.</li>
<li>Auto-hide on Accept or Deny with full keyboard accessibility.</li>
<li>Multilingual-ready and fully translatable (.pot included).</li>
<li>Preferences panel for per-script consent using <code><details></code>.</li>
<li>Add unlimited scripts with name, description, and JS code.</li>
<li>Scripts injected only on Accept; removed on Deny.</li>
<li>Consent stored securely in LocalStorage.</li>
<li>Backend settings for texts, styles, legal pages, and tab behavior.</li>
<li>Fully compliant with GDPR, CNIL, and ePrivacy.</li>
<li>Built with vanilla JavaScript – no jQuery dependency.</li>
</ul>
</li>
</ul>
Use the shortcode <code>[smile_contact_form]</code> to embed the form on any page or post.
<h3>External services</h3>
This plugin integrates Google reCAPTCHA v3 to protect the form from spam and abuse.
What the service is and what it is used for: 
Google reCAPTCHA v3 analyzes user behavior to block automated spam submissions.
What data is sent and when: 
Upon form submission, the following data is sent to Google: 
– reCAPTCHA token 
– User’s IP address 
– Your reCAPTCHA secret key
Links to terms and privacy policy: 
– <a href="https://policies.google.com/terms" rel="nofollow ugc">Google Terms of Service</a> 
– <a href="https://policies.google.com/privacy" rel="nofollow ugc">Google Privacy Policy</a>SMiLE Basic Web is actively maintained. If you find it helpful, consider supporting development through donations. Contributions and feedback are always welcome!

SMiLE Basic Web

SMiLE Basic Web is a versatile plugin combining features like Contact Form, sitemap generation, and configuration tools, all from unified interface.

IsSiY (Include second Sitemap into Yoast) WordPress SEO Extension vs SMiLE Basic Web