Hello everyone,

I am based in Japan and going to read mostly manga and novels.

There is a Kobo Forma at 164.30 USD (new) on Amazon and the Sage is sold at 232.14 USD on Rakuten.

Which one would you recommand given the pricing? I do not need audio books. What could be important is screen quality, battery life and interface/dictionnary functions.

Also could you use these e-reader to take notes? Like for example to note the translation of some Japanese words and characters on a manga?

According to my research until now, some people say the Sage is newer and better with better screen and performance overall but some other says Forma is lighter, has a better battery life and is more pleasant to use on a daily basis. What do you think? Is the sage worth the price difference of 70 USD?

Thanks!
All this is true, except for the part of the Forma being more pleasant to use; that's subjective and depends on the user. So you should decide which features are more important to you: screen and performance or weight and battery life.
I would suggest the Sage would be the better choice. The Sage has a slightly better screen, a more powerful CPU, a USB C connector and dual band WiFi. I own both and the lighter weight and better battery life of the Forma, to me, do not outweigh the advantages of the Sage.

I've played with using a stylus with a Sage but not something I use on a regular basis.
i would honestly recommend the kono libra 2 im using it and its fantastic so i wanted to compare it to the kobo sage and i found this good article that explains that kobo sage's price is a bit high for its value compared to kobo libra 2

this is the article:
https://ausdroid.net/2022/01/23/review-7-kobo-libra-2-vs-8-kobo-sage-which-e-ink-e-reader-should-you-choose/

and this is where i got the kobo libra 2:
Thank you for the URL.

Indeed Kobo Libra 2 seems really nice. However I would need a bigger screen to read comics (manga). 8" is the minimum.
The Sage supports the Kobo stylus, the Forma does not. Last time I used a Kobo (a couple years ago) they didn't have a built-in Japanese to English dictionary, just Japanese to Japanese and English to Japanese. You can add custom dictionaries with some effort. Japanese word lookup also wasn't the best as it would usually just select a single character rather than the word and couldn't deconjugate even when the whole thing was selected.

Although when reading manga you can't do dictionary lookup on words anyways because they're just images. You can manually lookup words but that's a bit of PITA. I would just keep a denshi jisho on the side.
Go for the Sage. I love mine. It is faster and has a better screen, which will be good for manga. The battery could be better, but is not as bad as people make out (I generally get at least two weeks of daily usage per charge (not reading manga or using the notetaking function)) and it takes no time to recharge, so it's not a big deal.

P.S. I am in Japan, too. Not that this fact has any bearing on this thread. ('_'