[Timja]

I would love a battery powered 32" E Ink screen that does nothing on its own, but lets me send it images to display.

But for that I guess I would have to give that thing access to my wifi? I wouldn't want that.

Any ideas if such a product exists and how one could use it shielded from the internet?

[cydmax]

A possible DIY way is to use a e-ink display connected to a Raspberry Pi and build a script to display content stored on a usb-stick connected to the USB-Port of the Raspi.