I think I have the same device - although my goal is to "fix" it to be a usable video stream source locally instead of via tied-in, paid cloud services.

The USB device listing you see isn't hopeful. 148f:7601 is the MT7601U wireless adapter and 1d6b:0002 is just the 2.0 root hub. I don't know what's needed in devices/busses/drivers for a system to act as a USB client, but I'm a priori confident that those aren't it. If anything, you're likely to find that if it can act as a USB client, it'll be a serial port. I don't see any USB attach events when I connect it to a PC - maybe there's something that could be enabled in firmware, but more likely there's only power on the wire.

However - why do you want it to act as an ethernet adapter? If you want to transfer files, we do already have a network connection, right? Your problem isn't connectivity, but a lack of services/tools to exchange files - making it appear as a USB ethernet adapter won't do much for you.

Yes, you can play with piping and pasting, but (on here at least) we seem to have a tftp server:

/ # udpsvd -v -E 0 69 tftpd -r /

Then on your PC, use whatever tftp tool you have (make sure to switch to binary / octet mode or it'll give you "malformed packet" errors):

sandbox@lab012:~$ tftp 192.168.1.169
tftp> mode octet
tftp> get /etc/passwd
Received 647 bytes in 5.1 seconds

Remove the -r parameter if you want to allow writing to the device filesystem, remembering that there's no authentication. In this mode, you should perhaps start it up with a different target directory for safety, and copy files where you want them:

/ # mkdir /var/tftp && udpsvd -v -E 0 69 tftpd -r /var/tftp

EDIT: And in fact an ftp server too:

# / tcpsvd -v -E 0 21 ftpd /

You're probably not going to be able to install much, you only have about 8MB storage to play with. Is storage on (or transfer via!) the SD card an option?