Oscar has a better ring IQ, is more versatile, and packs more of a punch on the inside. I see him getting the better of Taylor in exchanges around the mid-rounds, and maintaining distance with his jab, disrupting Taylor's in-and-out ambushes of furious combinations. Taylor was better than ever on the night against Chavez, and while he was brilliant, it's not at all hard to imagine Oscar similarly timing hard hooks between his rhythm and repeating the process of a hard-fought accumulative but climactic stoppage.
It'd be a good fight, I see Taylor giving Oscar problems with his blazing speed and busy workrate. Eventually though, DLH's jab, power, size/length would prove to be too much. Taylor would simply get hit too much.