Yes, it is possible to use cloud storage under the right setup, but it takes testing and very high-speed high bandwidth internet service. Not often recommended for media, more often used for project files.
So it would be best to import files. Do you know if it is possible to do this automatically everytime a file is uploaded to AWS?
Yes, you can try CloudBerry Drive and map it to your AWS S3 storage so it will show up as a regular HDD in your computer. But, video files are large and as Neil mentioned you need a very high-speed high bandwidth internet service to get it to "work".
I'll take a look
If you can get the media from AWS to appear in one of those four ways, then...yes! 🙂