Kirin (Fairy Tail) vs Harrison: who would win?

Harrison favored — Slight edge (~55%)

Kirin (Fairy Tail) · Fairy Tail · Base

Tier

5-B, up to 5-A

Attack Potency

Planet Level+, up to Large Planet Level

Speed

Speed Of Light, up to Ftl

Durability

Planet Level+, up to Large Planet Level

Harrison · Godzilla · Piloting Kiryu

Tier

5-A

Attack Potency

Large Planet Level

Speed

Superhuman, up to Massively Ftl+

Durability

Large Planet Level

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