Jetpack - Jetpack offers SEO and security plugins for Wordpress.
Yoast - Yoast offers plugins to improve SEO and optimize web sites and blogs.
WP User Manager - The most customizable profiles, community builder and membership WordPress plugin
WP Rocket - WP Rocket offers a caching plugin for Wordpress.
UpStream Plugin - UpStream Plugin is a free-to-use project management plugin that allows you to manage various types of projects right from your WordPress site.
Wordfence - Comprehensive security plugin for WordPress.