Logic Pro will only accept AU plugins, so your VST2, VST3, and AAX plugin files will have no impact on your libraries in logic.
AU plugins are plugins that end with a '.component' extension and are exclusive to Apple computers. These files are designed to run mainly in the apple software suite (Logic Pro X, Garageband, MainStage, etc).
The install location for AU plugins is as follows:
| Plugin Type | Mac |
| AU/Component | /Library/Audio/Plug-Ins/Components |
Within the Spitfire Audio app, you will not be able to change the install location of AU plugins, so the install location will always be consistent with the one above.
Once installed, you should be able to open your plugins in logic by creating a new channel track, selecting 'Software Instrument', and navigating to 'AU Instruments > Spitfire Audio'
More general information on library installation can be found in this article: Where is my library?