Jury-rigged Netcat from default Windows

Question

Something unusual: a code golf question with a purpose. I occasionally find myself in scenarios resembling the following:

Suppose you have two computers, A and B. Both of them have a fresh copy of Windows 10 installed. It comes with all the usual stuff, like notepad and paint and a browser, but no extras, like a Linux tools port. They ALSO have had Remote Desktop and the built in File Sharing removed/disabled. Computer A has one extra thing - a large-ish file (say, 10 MB) that you need to get onto Computer B. Computers A and B are connected over a LAN, but they are not connected to the internet. Their USB drives have been disabled, and they have no other data I/O peripherals. No disassembling the computers.

In the fewest possible steps, how do you get The File between LAN'd computers A and B, running default Windows 10, with no internet and no external storage devices?

I'm expecting something like "if you type such-and-such line into PowerShell, it takes a pipe and outputs it into a TCP connection", or "if you abuse the browser in such-and-such a way, it lets you host an FTP server". BUT, I'm open to surprises - as long as they're actually feasible.