Wado and Enma isn’t zoro swords to be fair
He carries both sword to carry shimotsuki wills
zoro is very own sword is sandai
In fact sandai is the only sword zoro sensed
that’s why sandai will be the last sword to become black blade
Enma and wado is meant for shimotsuki while sandai is meant for zoro himself
Sandai and zoro have much deeper relationships then Enma and wado
It make sense why the weakest blade ( sandai is great blade which is the lowest rank of all blades ) is gonna be the strongest blade. It doesn’t matter which rank of the sword or how high quality it is
Any blade can become the strongest
He carries both sword to carry shimotsuki wills
zoro is very own sword is sandai
In fact sandai is the only sword zoro sensed
that’s why sandai will be the last sword to become black blade
Enma and wado is meant for shimotsuki while sandai is meant for zoro himself
Sandai and zoro have much deeper relationships then Enma and wado

It make sense why the weakest blade ( sandai is great blade which is the lowest rank of all blades ) is gonna be the strongest blade. It doesn’t matter which rank of the sword or how high quality it is
Any blade can become the strongest