Verschränkung is derived from the noun Schranke, which means barrier or limit. The often red and white bar blocking passage over trains rails is also called Schranke.
With the picture of the railroad crossing in mind, when you cross your arms over your belly, we call it "die Arme verschränken".
The bridge to Verschränkung in quantum physics comes from the idea, that 2 things are entangeled in a way so that you can't operate on one, without influencing the other. In the case of crossed arms you notice that you will never find a single arm the same position, when the other arm is not involved.
Another possible english translation for Verschränkung is interlocking, which could have been another english name for the phenomenon, except that the entangled particles in quantum physics can be locally separated.
According to https://www.duden.de/rechtschreibung/verschraenken it goes back to forscrenchan in Old High German, which means something like to surround with a barrier or lock in.