In a recent CP+2023 interview, Kazuto Yamaki (President of Sigma Corporation) confirmed that Sigma will release a new 70-200mm f/2.8 lens with a different design:
Q: Will the art series 70-200 f2.8 lens that domestic users have been waiting for be released this year?
A: We have indeed heard voices in this regard, and we are currently working hard, hoping to let everyone see it sooner. In fact, for this lens, we have been considering its differentiated design, hoping to bring something different to users, which is why we have not launched this lens yet. (source)