Recommend me an eink reader that I can transfer files to from my phone

https://lemm.ee/post/27801813

Recommend me an eink reader that I can transfer files to from my phone - lemm.ee

Preferably not a Kindle because I dislike Amazon spyware but if it must be then it must be. My use case is downloading PDFs and epubs onto my phone and transferring them to the eink display.

Kobo ereaders are great, when I’m on trips I download epub files on my phone, plug the ereader to my phone via USB, copy-paste the books and it just works. No need to install anything on the Kobo.
I got a kobo recently and noticed bad performance with some epubs, very slow loading times and page flips. If I convert the to kepub with calibre (requires a plugin) then it’s super fast but I don’t think there is calibre for phones.

I had trouble with a couple fan made books. Usually it comes from the .epub being set up improperly, so that the chapters are not set properly, causing it to reload the whole book every page turn.

Havn’t run into it with any purchessed .epubs

I thought so too, the main problem I found mentioned online is a file with only one chapter for the whole book. But mine was fine and was an official publication. I even tried a repair tool to no avail. Converting did the trick though.