First, delete all previous plugin versions from your computer, including their sound content (the .instruments folders), and scan your plugin list in your DAW.

Second, move only the .vst, .vst3, .component, and/or .dll files to their corresponding plugin folders and put the sound content on your external HD of choice.

Third, scan your plugin list in your DAW, load the plugins, and click on "Choose a folder...". Select the corresponding .instruments folder to load the sound content.

For example, if your plugin is Virtual Vocaid, you want to choose the folder Virtual Vocaid.instruments.