I just got a boox e ink tablet. It runs android. I have a sideloaded manga reading app and Google books installed. epub books (found easily on Yandex) can be uploaded to Google books from my phone.
Oh nice! Yeah this is 100% the best way to go. I use the app Mihon for finding/reading manga, its basically the same as tachiyomi before it got shut down.
The one I use is the Boox 7.8" Nova Air2 eReader. I chose one without a color screen. The color screens are cool and all, but for black and white content, the color layer makes the white more of a grey color. For that reason I don't recommend the color e ink quite yet.
The 7.8" screen is literally the perfect size for manga. It feels perfect.
I have a boox page and i love it. I don’t use it for reading manga but i haven’t tried it so can’t speak on whether it would be good or bad. It’s amazing for books though, great battery life and SD slot which were huge for me. It also runs regular android so I use Koreader to read books and you could definitely download Mihon to read mangas.