Some plugins not listed

if they do not show in the list then they are either network activated already, or designed to be network activated only (via a header in the plugin file). Because of this they can’t be managed on a per-site basis.

Ok, thanks. What is the header in the plugin file? There are a few custom plugins that could be edited to add any code that would allow them be switched on or off per site.

https://developer.www.ads-software.com/plugins/plugin-basics/header-requirements/

See the ‘Network’ part.

Ok, thanks