Zechariah vs Hiruhiko: who would win?

Zechariah favored — Slight edge (~55%)

Zechariah · Invincible · Base

Tier
9-A
Attack Potency
Small Building Level
Speed
Relativistic
Durability
Small Building Level

Hiruhiko · Kagurabachi · Base

Tier
9-A, up to 8-B
Attack Potency
Small Building Level, up to City Block Level
Speed
Massively Hypersonic, up to Massively Hypersonic+
Durability
Small Building Level

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