Mud Slaad vs Maiko Plasma: who would win?

Maiko Plasma favored — Slight edge (~55%)

Mud Slaad · Dungeons & Dragons · Base

Tier
9-A
Attack Potency
Small Building Level+
Speed
Hypersonic+, up to High Hypersonic+
Durability
Small Building Level+

Maiko Plasma · One-Punch Man · Base

Tier
8-C
Attack Potency
Building Level
Speed
Supersonic, up to Massively Hypersonic+
Durability
Unknown

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