How can I quickly transfer many files from my Android device to the PC, without USB cable or WiFi?
Regular bluetooth would require to transfer every single file manually.
After pairing, use Bluetooth software on PC to browse file system of device (almost all software work as OBEX FTP client). You can copy an entire folder from device to PC. Done!
While a good bluetooth app is probably your best bet, I can think of 2 other ways that answer the question:
Shareit application can be used for the transfer of files from PC to Mobile and viceversa
It does not require wifi or cables. It Would create a hotspot(have to create a network in mobile and suggested to turn off your mobile data) then you can transfer from PC to Mobile and vice versa.
(Make it as a comment as i dont have enough reputations)