In-code, you can check the 'GetDeviceBaseName()', other parameters, and even which rendering API is being used to selectively activate or deactivate code. And I highly recommend doing that so you can work from one consistent codebase for easier project management across multiple platforms.
Unfortunately, you can't do this with plugins and will only receive an error message if a plugin isn't available for the platform you are running on. This is one of the biggest drawbacks to plugins and why it's best to try and avoid them if you want your project to be more cross-platform. Plugins typically lack support for the same platforms that AppGameKit does support, often only supporting one platform and sometimes only one bit format on that platform, so they are inherently more restrictive/limited for projects. You also risk introducing runtime dependencies with plugins that would otherwise not be required for your project, unless the plugin is properly compiled to avoid it.
So try to do as much in AppGameKit code as you can or if possible, work with plugins that support all of the platforms you intend to target.