Ghidorah Rei vs Yukinori Shinohara: who would win?

Ghidorah Rei favored — Slight edge (~55%)

Ghidorah Rei · Godzilla · Base

Tier
LOW 7-C
Attack Potency
Small Town Level
Speed
Speed Of Light
Durability
Small Town Level

Yukinori Shinohara · Tokyo Ghoul · Base

Tier
LOW 7-C
Attack Potency
Small Town Level
Speed
Massively Hypersonic
Durability
Small Town Level

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