Also sharing the KINGJIM Digital memo Pomera DM30. It has a 6 inch eink screen attached to a folding keyboard, very similar to Freewrite except it has no internet connection function. It's very bare bones, just a text editor and a USB slot for you to write your files on. You can transfer the text via QR code as well (which works shockingly well). It's a very elegant package that's worth picking up if Freewrite interests you, but you don't want to pay whatever they're asking these days.
I used this a lot when I was traveling and wanted something slim and light to type on. It's a Japanese product that works with an English keyboard 98% of the time. There are little quirks in the input, for example if you hit a random function button and it converts back to Japanese text input. But I've done some good writing on this machine and I just don't use it now because I'm at home all the time and prefer my Yoga Book.
https://www.amazon.com/dp/B07CYTVH4Z/ref=cm_sw_em_r_mt_dp_24a9Fb5YZP313?_encoding=UTF8&psc=1
I ordered mine back in March 2019 and should be getting it soon. I do a ton of traveling and camping so I needed something with a huge battery life and something I can just open up and immediately start writing. I'll see how it fits in my life.
Although, if I could do it all again, I'd just get this thing
https://www.amazon.com/KINGJIM-digital-memo-Pomela-Silva/dp/B07CYTVH4Z
Perhaps you will be better served by an e-ink typewriter as you said. I have the Pomera DM-30 ( https://www.amazon.co.jp/dp/B07CYTVH4Z?language=en_US ), and the keyboard is nice enough if you're typing in English.
The cost of the device + shipping to Europe was a very reasonable 214,48€. The AA-Battery problem was solved using a pair of USB batteries with AA form-factor, like these: https://www.amazon.de/dp/B00D2V2O44?language=en_GB
I just bought a Boox Note2 and it came with a free keyboard. If you’re looking for something simple, similar to the Freewrite that doesn’t save data in someone else’s cloud check out the King Jim Pomera Dm30 on Amazon.