Android 19 vs Shadorah: who would win?

Shadorah favored — Slight edge (~55%)

Android 19 · Dragon Ball · Base

Tier

LOW 4-C, up to HIGH 4-C

Attack Potency

Small Star Level, up to Large Star Level

Speed

Hypersonic+, up to Massively Ftl+

Durability

Small Star Level, up to Large Star Level

Shadorah · Godzilla · Base

Tier

4-C

Attack Potency

Star Level

Speed

Subsonic+, up to Massively Ftl

Durability

Star Level

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