Kiyama Harumi vs Shion Madarame: who would win?

Shion Madarame favored — Slight edge (~55%)

Kiyama Harumi · Toaru Majutsu no Index · Base

Tier
9-C, up to 8-B
Attack Potency
Street Level, up to City Block Level
Speed
Average Human
Durability
Human Level, up to Town Level

Shion Madarame · Tokyo Revengers · Base

Tier
9-C
Attack Potency
Street Level
Speed
Unknown
Durability
Street Level

A heuristic estimate from normalized VS Battles Wiki stats: tier, attack potency, speed and durability.