When we look at the great classical authors, like Tanizaki, Kawabata and Mishima, the picture is not so different, as these authors are covered well in all three languages. Natsume Soseki has been well-covered in French, but not so much in German. Anyway, generally speaking as translations go, the French are much more Japan-minded than the Germans.
Nagai Kafu is disappointing in both languages, Akutagawa does not differ much. Striking is the German interest in Inoue Yasushi. You can find several classical novels not available in English, as Der Tod des Teemeisters (The Death of the Tea Master), a compact historical tale about the mysterious circumstances surrounding the suicide-on-demand (by Hideyoshi) of Sen Rikyu; Die Eiswand (The Ice Cliff), a long novel about a love triangle and about mountain climbing; Der Stierkampf (The Bullfight), an early story about a newspaper reporter organizing a bullfight in the chaotic years after the war; and Schwarze Flut (Black Tide), the mystery surrounding the death of a public figure. Of course, the famous historical novels and stories (such as Das Tempeldach) are also available, making a good assessment of this author about human loneliness and elegiac failure possible.
Also in German, some novels by Oe Kenzabuto not available in English have been translated: Der Weise Regenbaum (Women Listening to the Rain Tree) or the trilogy Grüner Baum in Flammen (Green Tree in Flames). Another "difficult" author from whom much more has been translated - this time into French - than English is Nakagami Kenji: Milles ans de plaisir, La mer aux arbres morts, Miracle, Hymne, and Sur les ailes du soleil.
While Murakami Haruki has on the average been as completely translated in both languages as in English, in the case of that other "Murakami" author, Murakami Ryu, in French we find many novels not available in English: Ecstasy, Raffles Hotel, Melancholia, Thanatos, Kyoko, Lignes, Parasites, La Guerre commence au dela de la mer, and Topaze. In other words, Murakami Ryu is one of the best translated Japanese authors in French (of course the novels available in English have also been translated into French).
In French, there are even novels by authors not at all available in English. Two authors to whom much attention has been given are Ikezawa Natsuki and Kawakami Hiromi. I saw their names for the first time on these French translations! Ikezawa (born 1945; I still have to read him!) writes about the contrast between civilization and nature - three of his stories appeared in English but I have never seen them, while at least seven of his novels are readily available in French. Kawakami Hiromi (born 1958; also new to me) is a popular woman writer who received the Akutagawa prize for Tread on a Snake. Nothing is available in English, while in French we have five novels.
Other (often young) Japanese authors only available in French (and sometimes German) include Wataya Risa, Tsuji Hitonari, Machida Ko, Oba Minako, Kitano Takeshi, Matsuura Rieko and Ishida Ira, to name a few. I was surprised at the richness of choice. Even quite a lot of thrillers are available, as Hara Ryo's classic Nuit sur la Ville.
[To find these books on the internet, the best way is to go to the French or German Amazon. To find them in bookstores in Japan, check out the large stores in Tokyo as Maruzen (Oaza and Nihonbashi) or the Kinokuniya in Times Square (Shinjuku)]