No, because my brother does not do torrenting. So we would need to install a client, and create a magnet for the file, which would be sent across some messeging app or email, which in itself is pretty complex. And the local discovery doesn't always work, i works often, but not always, so in doing that i would look forward to discovering is IP, as we don't do static local IPs anymore (steam does all the game linking, so what ever)
All that setup wouldn't have been completed before the mod-file was transferred to a USB stick, and flung through the living room. And no, downloading the mod again is still not as fast. You would have to find the page in firefox, even if it is open, verify that i was the right one, copy the link, certainly only of the page (as direct link of the file does not always work, maybe some per-deteriation of hosting server is done on some sites, i don't know) and then again decide and communicate your intended medium of transferring the link, so he could watch it, and then start the transfer, which is almost guaranteed to be slower than the speed of my decent USB stick.
I have in fact a permanent mounted USB stick on our router, with all PCs linked to it, which is often how we do it. However it was currently full, and instead of going through the effort of judging the importance of said files belonging to other members of the household, i just grabbed a nearby USB stick.
TL;DR: No, it's not faster. For a single transfer, between two random(!) people, USB stick is always faster.