We all have our slow moments, don’t we?
The nuances of plugin activation on WP multisite wasn’t immediately obvious to me and so it took a bit for me to figure out. In my defense, it’s not labelled clearly. But regardless, I hope that admitting this in public can save somebody else time.
“You don’t need to network activate all plugins on your WordPress multisite network. For example, if you want to use a plugin on the main site, then you need to install it and then switch to the plugins page for your main site to activate the plugin.”
WPBeginner
My confusion stemmed from years of using vanilla WP, where you (almost) always activate a plugin right after installing it. Later, when I was first adding plugins on a multisite, the only option after install was to Network Activate.
So I always network activated.
All the subsites got every plugin and I just edited their admin menu to hide what I didn’t want them to have access to.
I didn’t know you could skip network activate, but still turn it on elsewhere for the primary site (or any specific subsite).
There isn’t a button explicitly for that (e.g. Activate, or Activate on Primary Site). Instead you need to leave the plugins page without clicking Network Activate, go to the primary site’s or subsite’s plugin page, then you can click Activate there.
So that’s how to activate a plugin on a specific subsite but not the entire network.