Im asking this because Madara got both of them when he implanted Hashirama's cells in his body.Would it work for Sasuke too?
what Madara did was combine the chakras of Indra and Ashura, he already had the chakra of Indra since he was a reincarnate and added Ashuras chakra by attaching Hashirams cell(who was a reincarnate of Ashura). Meaning he essentially combined those chakras to become more or less like the six path. But in the case of Sasuke he gained the other half of the chakra from Hagromo directly so he already has the missing part to become the six path. Therefore he cant awaken a second reningan, i.e he has already gotten Hashirams cell when he got his missing arm attached(that was made from Hashirams cell)
I'm not 100% sure if it would because Madara awakened his rinnegan because at the time he and Hashirama were the incarnates of Indra and asura. But now it's Naruto and Sasuke who are so if Sasuke got a Hashirama arm he wouldn't have the necessary blend of chakra to awaken the second rinnegan