Multisite Matrix

WordPress Multisite's own Network Admin lets you see which plugins are network-activated, but it has no built-in way to see which plugins individual site admins have activated locally, one site at a time, across a whole network. Multisite Matrix closes that gap. What it does

• Adds an "Active on Sites" column directly to the existing Network Admin > Plugins list, showing at a glance which sites have each plugin active locally.
• Adds a dedicated Plugin Matrix page (Network Admin > Plugins > Multisite Matrix) with a full plugins-by-sites table: every installed plugin as a row, every site as a column, so you can scan the whole network's plugin usage in one screen.
• Flags plugins that are installed but active nowhere in the network — a quick way to spot cleanup candidates before a security or performance audit.
• Distinguishes network-activated plugins (active for every site by definition) from plugins activated locally on individual sites.
• Links straight through to each site's own Plugins screen from the matrix, so you can act on what you find without hunting for the right site first.

Why On a network with more than a handful of sites, "which of our 40 sites still has that old SEO plugin turned on" is a real, recurring question that WordPress core simply doesn't answer without opening every single site's plugin screen by hand. Multisite Matrix answers it in one page load. How it works Data is read directly from WordPress's own site and network options — nothing is sent anywhere, no external requests are made, and the plugin makes no changes to which plugins are active. The plugin-to-site mapping is cached for an hour (via a site transient) and automatically refreshed whenever a plugin is activated, deactivated, or a site is added or removed, so the matrix never depends on a manual rebuild. Requirements Multisite Matrix only does anything on a WordPress Multisite install — on a single-site install it stays completely inactive. It can only be network-activated (not activated on an individual site), and its screens are only visible to users with the manage_network_plugins capability (network administrators).

1.2.4

• Source strings switched from German to English (WordPress.org convention) so the plugin can be properly localized.
• Added translations for German, French, Spanish, Italian, Dutch, Portuguese (Brazil), Polish, Russian, Japanese, and Chinese (Simplified).

1.2.3

• Renamed internal function, class, and option/transient names to use a unique "MULTMA"/"multma" prefix, per WordPress.org plugin review feedback.

1.2.2

• First public release on WordPress.org.