Should be that way, Zoro has nothing to do with wings while Sanji can fly, also that was a figure of speech like "right and left hand","pillars of the crew" etc. So... Whatever as long as the general meaning is always the same.
Now that I think about it this could just be Oda preparing to deliver a troll move aka Sanji is the wings, but.. Zoro stays as the right hand then Jinbe enters as left hand. And about Yamato, if she joins, she can become the tail of the crew oflr some other trollade from Oda, he could even make her the third arm. Ok, this is starting to sound weird now.