Aero vs Isolde: who would win?

Isolde favored — Slight edge (~55%)

Aero · Marvel · Base

Tier

6-C

Attack Potency

Island Level

Speed

Hypersonic

Durability

Island Level

Isolde · Nanatsu no Taizai · Base

Tier

6-C, up to 4-B

Attack Potency

Island Level, up to Solar System Level

Speed

Sub-Relativistic

Durability

Island Level, up to Solar System Level

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