The third version of the AxE says that you can put CC-BY-licensed material into a product released under the ORC license.
If so, I'm really puzzled as to why Paizo isn't just helping itself to chromatic dragons, glabrezu, duergar, aboleths, alignment, drow, etc, etc, just by releasing a new version of PF under an ORC license that uses elements of SRD 5.1 under its CC-BY license, rather than doing this huge expunging project. Their own lawyers seem to say that's okay.
WotC hasn't released the 3.5 SRD as creative commons. Aside from the game mechanics, the one noticeable difference between the 5.1 SRD and the 3.5 SRD is that 5.1 SRD doesn't include any description of the monsters, including the drow.
If you use the CC-BY version of the 5.1 SRD you can use the term "drow" and copy the mechanics, but all of the fluff of the drow is lost.