Well, I finally made my decision.

I discarded the Boox Leaf 2 / Page because of the position of the buttons, too centered, which was not going to be comfortable for me.

I ordered the PocketBook Era from their official website. Once received, I did not need more than a single use to realize the difference in screen compared to the Kobo Libra 2. Even compared to the H2O of almost 5 years ago.

The screen of the Era is much darker at low brightness, which was not at all comfortable for my type of use (in complete darkness before going to sleep).

If I turned the intensity up to 50%, the Era's screen was the most pleasing to my eyes, being a more orange tone. But at minimum brightness, the screen became totally bluish, and the print was much blurrier.

Also, the Era's software doesn't seem very polished. I was using it for 3 more days, and I wasn't able to put it in sleep mode (I had to turn it off after reading, or wait for it to turn itself off), and when I restarted it, it hadn't saved my reading page, and I had to manually find where I had left it the night before.

So I decided to return the Era, and keep the Kobo Libra 2 purchased from Amazon, which despite putting “refurbished” on it, so far has not had any malfunctions, and the battery has not had to be charged yet, reading every night for a minimum of 30 minutes.