I don't think there is a standalone flash player for Android. But even if there was it would mean that people need to install that first before starting your app.
I believe the slowness you experience as nothing to do with webviews but simply with the resources available on a mobile device (1/3rd minimum of the cpu device and 1/10th of the memory).
You can check if that is the case by simply trying to launch your swf from the native web browser of your device and see if its better. If not, the problem is really your device.
You will probably need to create a strip down version of your flash for mobile devices.
Beside you should know that adobe plans to stop flash for mobile devices : http://www.fiercemobilecontent.com/story/adobe-confirms-flash-support-android-ice-cream-sandwich/2011-11-21
Good luck