i think you could make this with tunisian. when it gets the the split, you could keep working half the stitches until both halves are long enough and then start stitching across the entire piece again at the other end.
Middle sweater with a different ribbed bottom.
Translate to crochet. Ravelry: Art Deco Cardigan pattern by Helen Hamann Holy cow this is gorgeous. If I could do entrelac.