The Gemara says that the gid hanashe was forbidden to Bnai Noach. Presumably this means, Yaakov Avinu, his family and the Bnai Yisrael until the Torah's time not the non Jews. (Maybe Avraham and Yitzchak too?)
Where is the issur repeated after matan Torah? Does it have to be repeated?
We discussed this issue in the online audio Shi'ur to Chulin 91a.
The opinion that Rebbi Yosi bar'Rebbi Chanina is quoting is expressed in the Mishnah later (100b). This opinion maintains that the Isur of Gid ha'Nasheh applies to Benei Noach, as you write. Although the Gemara in Sanhedrin (59a) says that every Mitzvah that was taught before Matan Torah (to Benei Noach) and was not repeated at Matan Torah applies only to Jews (such as Gid ha'Nasheh, as the Gemara in Sanhedrin specifically mentions), this opinion either argues with that Klal, or it means that the Isur of Gid ha'Nasheh applied to Benei Noach *until* Matan Torah (as the Gemara here is referring to Yosef and his brothers, who lived before Matan Torah).
Y. Shaw
The other mitzvah that occured to me as not being repeated is pru u'revu. Is it repeated anywhere after matan Torah. Is it a mitzvah for Jews and bnei Noach or just a beracha for them?
See Tosfos in Chagigah (2b, Lo Sohu), who seems to say that Benei Noach are Chayav. See Maharsha there who asks that we do not find the Mitzvah of Peru u'Revu repeated at Matan Torah. See Turei Even there (in Avnei Milu'im section) who explains that Tosfos means to say that Kena'an had the Mitzvah until Matan Torah. See also Mishneh l'Melech, Hilchos Melachim 10:7.
D. Zupnik