Onyx BOOX? They run Android. Poke 5 is nice.
Ereader
For all things ereader
Boox devices can run Moon+ but it's not great on an eink screen.
KOReader can sync reading position across multiple devices with the progress sync plugin but you need to handle syncing actual book files to each device yourself. That's easy enough with one of the many android file sync apps though.
Oooo thanks for the details!!
I'm definitely looking at kobo readers now. Do you have any handy links handy for posterity/future people looking for ereaders? Otherwise I'll go looking for write ups on how to set this up before I pull the trigger
Do you have any handy links handy for posterity/future people looking for ereaders?
Unfortunately I don't, I had to trawl through most of the ereader subreddits to get the lay of the land. I ended up buying a Boox device personally, I wanted faster hardware than the other dedicated e-readers were offering and that was the best option at the time.
I can recommend the Boox Nova Air v1 if you're looking for an ~8in KOReader platform, I've been pretty happy with mine. I don't really use the built in apps much, just KOReader and my sync app to sync with a B2 cloud storage bucket. At the time this was best 8in 300ppi Android option available.
It’s not an E-reader but I use a Google Nexus 7 tablet from 2013 with LineageOS and a matte screen protector. This works with Moon+, is great for PDFs and epubs, costs about 20 bucks, and syncing and loading books is very easy since it’s Android. Not what you asked for but might be a good second option if you can’t find an E-Ink reader that does what you need.