I've just received a hard drive with about 3/4tb of files. In some cases I have full folder structure from BPAV on, in some cases just the CLIPR and TAKR folders and contents, in some cases just the folders and contents that would normally be in the CLIPR folder, and in some case just the mp4's. So far Avd, FCP and Clip Browser won't see or import anything outside of full BPAV structure. All files will come in using Premier Pro or Vegas. Any hope of getting these into an Avid. Tried exporting just clips(not sequences) from Premier Pro, crashed my system twice.
If you put the .mp4s into one folder and add that folder as a source in XDCAM Transfer v 2.12 or higher (for FCP), the files will be recognized and importable.
You can also use Sony's Clip Browser or XDCAM Browser software to manually import the .mp4s into a new BPAV. Highlight a location ion the 'Explorer' window on the top left, select File-->Import, browse to the .mp4s and import them. When you're done you'll have a new BPAV with new metadata and a rebuilt folder structure. If you're on a Mac you can use the search window in the Import dialog to narrow the search to ".mp4" and it will show you all the .mp4s in a given location. This is helpful as it allows you to do multiple clips at once, even though they may be in their own folders..
If you do a search on this forum the above process has been covered in detail in previous posts.