Third Wave vs Tidal Wave (Dreamwave Unicron Trilogy): who would win?

Third Wave favored — Slight edge (~55%)

Third Wave · Kaiju No. 8 · Base

Tier
7-A
Attack Potency
Mountain Level+
Speed
High Hypersonic
Durability
Mountain Level+

Tidal Wave (Dreamwave Unicron Trilogy) · Transformers · Mirage

Tier
HIGH 7-A
Attack Potency
Large Mountain Level
Speed
Superhuman, up to Massively Hypersonic+
Durability
Large Mountain Level

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