Weather Report vs Isu: who would win?

Too close to call

Weather Report · JoJo's Bizarre Adventure · Base

Tier

8-C, up to 6-C

Attack Potency

Building Level, up to Island Level

Speed

Ftl

Durability

Building Level+, up to City Level

Isu · Assassin's Creed · Technologically

Tier

8-C, up to 5-B

Attack Potency

Building Level, up to Multi-Continent Level

Speed

Hypersonic

Durability

Multi-Continent Level, up to Planet Level

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