Swordsmanship is like gender identity.
Take King and Cabajii.
They both have things "besides their swordsmanship".
They both have fire abilities.
Cabaji has acrobatic moves.
King has hair-comb moves.
Etcetera.
The only difference is one identifies as a swordsman while the other doesn't.
Zoro says if it really comes down to it, he might perform things that are outside of swordsmanship.
This is fine because he identifies as a swordsman anyways.