According to a source they’ve cast Bex Taylor-Klaus as Sin; whom is known in the comics as the young adoptive daughter of Dinah Lance.
Her character will be “Sin,” the Gail Simone creation who first appeared in Birds Of Prey #92 back in 1999. Obviously, this version of the character is older than her comic book counterpart.
As you can tell, Bex is neither a child, nor a young asian girl. And on top of that is apparently has no scenes so far with Laurel. I get that they’ve aged her up but if Arrow really wanted a runaway youth, couldn’t they have gone with Mia, who makes ten times more sense than this.
Anyways Bex Taylor-Klaus will appear in the third and fourth episodes of the new season, and we know so far that her scenes also involve Colton Haynes’ Roy Harper. Lets wait and watch for more details.