The funny thing about your post is thought you did something.
What is headcannon about my post? Zoro is proof a character doesn't need to hold a weapon in their hand to add haki to it. Blades coated in blackened CoA haki looks the same as black blades.
Most characters don't have black blades even among top tier characters and we know GB can use blackened haki so it's reasonable to believe he doesn't have a black blade and just coated with blackened haki for his battle. Since we didn't see his sword prior to battle you can't say it's black blade.
You post is complete nonsenses. Most characters in the mangs haven't changed from man to women. You haven't provided any facts showing why that is a possibility for Zoro's dad.
Do you understand the difference between our post or is it too hard for you to comprehend?