Curate, connect, and discover
After we learnt that there were ~25 people who left Wano with Kozaburo, but that only ~10 people stayed in Shimotsuki Village, I always imagined that Tashigi might be decended from the remaining 15.
I still like to think that Shimotsuki Kozaburo, Shimotsuki Furiko and someone else (who didn't stay in Shimotsuki Village) may have been cousins, later having children and grandchildren who would end up being third cousins- the grandchildren being Zoro, Kuina and Tashigi.
I feel like it would make sense for Tashigi to look similar to Kuina for this reason. We still don't know if Tashigi has a last name, and it is possible that she could be a Shimotsuki considering her connection to swordsmanship.
It’s been almost 20 years and i’m still wondering why Tashigi and Kuina are so look alike and this fact is remarked every time. I think most of us agree that they’re not the same person, but there must be a reason why they look so similar and at this point in the story it continues to be highlighted every time she and Zoro meet. I mean...what's the point? Is it supposed to have any relevance? Or is it just used as another gag?