Google searches nearly all report $HOME/.config/obs-studio/plugins as the directory to install plugins for OBS Studio on Linux. This is almost correct, but misunderstands the question I was asking. If you’re a developer, you’re looking for the place to put the .so files, not the place to put the plugin. Plugins have a folder structure.

Thanks, Gemini, for giving me the clue I needed. (I still have no respect for AI.)

Plugin Structure:
Within the plugins folder, you’ll typically find subfolders for each plugin, often with a structure like plugin-name/bin/64bit/plugin.so or similar.

Also, it appears the folder name and the name of the .so file have to match, though you can include or omit the lib prefix common on shared object files on Linux.

I’m sure this is in the OBS documentation somewhere… right?