Welt Yang vs Emerl: who would win?

Emerl favored — Slight edge (~55%)

Welt Yang · Honkai: Star Rail · Post-Sea of Quanta

Tier

3-C, up to HIGH 1-B

Attack Potency

Galaxy Level, up to High Hyperverse Level

Speed

Ftl, up to Infinite

Durability

Galaxy Level

Emerl · Sonic · Ultimate Emerl

Tier

3-C

Attack Potency

Galaxy Level

Speed

Massively Ftl+

Durability

Galaxy Level, up to Complex Multiverse Level

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