My favorite from the list would be
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. It's not technically a Japanese game (originally written in English), but plays in Japan and kinda pretends to be Japenese... It's probably the highest quality Ren'py game there is. Contrary to most games on that list, though, it doesn't have voice acting.
The undisputed champion of sad stories imo would be
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. I haven't played the remake, but I sure found it hard to put down the original at the time.
I also remember having lots of fun and feels with
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, although the translation at the time was pretty dreadful. Apparently they revamped that, so maybe I'll take another look at it some time and finish that last route.
If you like that, you can also check out
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, which gives you two additional scenarios involving two of the supporting characters from Edelweiss, plus a third scenario, which is basically just a big threesome scene with those two girls. Personally, I loved it.
Beyond that, many games on the list should be quite good, with the better ones being higher up. Most of those with an English translation should be here on the site somewhere.