Using wp single login you can easily add the functionality to allow only single login per user.
More Plugins
-
Kognetiks Chatbot for WordPress
-
Ruven Themes: Sharing Links
-
Social Feed Gallery
-
Database Backup for WordPress
-
Advanced Shipment Tracking for WooCommerce
-
Woo NovaPoshta Shipping Method
-
Image Optimizer by 10web – Image Optimizer and Compression plugin
-
Beehive Analytics – Google Analytics Dashboard
-
ImageRecycle pdf & image compression
-
Captcha Spam Blocker
-
Smart Grid-Layout Design for Contact Form 7
-
Remove links from comments
-
Starbox – the Author Box for Humans
-
Hide Broken Shortcodes
-
Customize WP-Login
-
Simple Google Photos Grid
-
Accordion Toggle
-
WPshop 2 – E-Commerce
-
Clearblue® Ovulation Calculator
-
Simple Posts Ticker – Easy, Lightweight & Flexible