I'd always been curious about R Dovid Frankel, author of the monumental commentary Korban HaEidah, and the teacher of Moses Mendelssohn (according to a recent article, Mendelssohn's philosophy is based to some extent on the teachings of R Frankel, See Gad Freudenthal, "Rabbi David Fränckel, Moses Mendelssohn, and the Beginning of the Berlin Haskalah: Reattributing a Patriotic Sermon (1757)," European Journal of Jewish Studies 1:1 cited here). A nice biographical article was written by Max Freudenthal from the David Kaufmann Sefer Yovel from which I take the following "Google translated" excerpts:
Frankel "coat of arms" [?!] from seal of letter.
He chooses the words to the title of his Yeruschalmi commentary Korban ha-Edah, because the initial letters of the names of his parents, Naftali Hirsch and Edel (KorbanN Ha Edah) are intertwined in that, and moving sentences he devoted to the dead father during in the obituary added in the 2nd edition.
He showed himself to be stern and firm solid teacher who held captivated the attention of students without ceasing to his questions and discussions and their mental faculties constantly spurred sharply. ... But with just as much energy, the rabbi also watched over the outside caring for his charges in the community. They all had their regular weekly support in money and free meals in the families, and his own house went all others in setting a good example. There was even the scholars of the night lit up a room and heated through, in what could give every three hours alternately eager to study, and even out the teacher's care felt that they always ready to make the body comfort hot water rose. Here they could also use the books to treasure that David Franckel possessed. For the possession of books was so expensive that poor students who could treat him, and even absolutely necessary for studying and expensive works were sold out so that the lack of it in the academies is very palpable and perceptible made.
Frankel had many chiddushim on Talmud Bavli and the Halachic codes, his father insisted he publish the Yerushalmi commentary first.
He has a hard time connectin Frankel and Mendelssohn, but does claim that Frankel was involved with the republishing of Moreh Nevuchim for the furst time in 200 years and transferred his love of the Moreh to Mendelssohn. He searches hard for secular knowledge in the part of R Frankel but could only come up with two half-scientific statements.
He cites two bans from Frankel apparently concerning some form of games, and a problem concerning servants?:
Demnach, weil sich Männer, wie auch Weibs-Leuten befleissen, DienstBothen zu verführen, wie gethan hatt Jacob Radegast seine Frau mit Samuel Moses sein Gesinde, wie auch Nathan Beer seine Tochter mit Kauff-Mann Jacob seine Magd, wie auch ein solches dem Moses Abraham Hirsch begegnet hatt, und sie suchen dadurch die Hausswirthe zu Ruiniren; dieses allein ist noch nicht genug; So geschieht, alss Ehr-Leuten-Kinder anleitung gegeben wirdt, mehrer Schlimmes zu thun, auch solche, wo sie mit Diebe Theillen, giebet es, mehrer Unzucht darbey: sie Stehlen, sie leben unkeysch, sie Stecken andre Leuten-Sachen in ihre Säcken, Sie verläugnen den Herrn und Sprechen: Er seye es nicht. Solche Kinder seinen Leydiger ihre Eltern.
Someone wh understands German can probably find more.
[A Mendelssohnian Korban Eidah might be his commentary to Nedarim 9, that interprets Ben Azai's - זה ספר תולדות אדם as Kol HaTorah Kulo to have a universalist sentiment that all people are created equal which opposes R' Akiva's particularist - ואהבת לרעיך כמויך which seems to only include Jews . But this is not a great proof because it is called for by the text.]