You used to be able to connect two PC’s together via the parallel port. I had to do this once to re-install Windows 95 on a laptop with a hard drive and floppy. It was painfully slow but it worked.
Up to 2MB/s effective throughput, better than 10M Ethernet. Likely it was slower for you due to other limitations.
This could be done on Amiga too, using parnet https://crossconnect.tripod.com/PARNET.HTML
I recall it being easier to set up than a dialup modem (since the latter also required installing a TCP/IP stack)