Bigger screen is better for manga, so Aura One will be better if you want to choose one of these two.
You can also look at Kindle espessially Oasis2, there is a bit smaller screen (as on Kobo H2O) but a bit better software as well. Frontlight is without BlueFilter on Kindles though.
For comparison I found this table is helpful:
https://www.the-ebook-reader.com/ebo...omparison.html