I've already made the point in the Diarmuid/Kojiro matchups that two spears can quite easily block three simultaneous sword swings, and Scathach has a spare half dozen to stab him with while he does that, but he has nothing that can block Gae Bolg.
In skill/technique, who knows? Kojiro's good enough to warp reality with his swings, but by Scathach's own admission, she's skilled enough to kill gods with nothing but a spear... blow. However that works.