User blog comment:UniverseAwesome777/Guess The Matchup: Ultimate/@comment-35104290-20190110142755

Based on How your brain works my guess is:

Dust vs Lucina

Shantae vs Yang

Weiss vs Sub Zero (Long Shot but makes Sense)

Darkspine Sanic vs Excalibur Sanic (This is the most obvious of them all)

Strider vs Akame

Pittoo vs Bass