Alastor vs Kuro (Puella Magi): who would win?

Kuro (Puella Magi) favored — Slight edge (~55%)

Alastor · Hazbin Hotel · Base

Tier
LOW 7-C
Attack Potency
Small Town Level
Speed
Subsonic, up to Supersonic+
Durability
Building Level, up to City Block Level+

Kuro (Puella Magi) · Puella Magi Verse · Base

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

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