Argento Pocoron vs Laser Lance: who would win?

Laser Lance favored — Slight edge (~55%)

Argento Pocoron · RWBY · Base

Tier: 8-B
Attack Potency: City Block Level
Speed: Relativistic
Durability: City Block Level

Laser Lance · Ben 10 · Base

Tier: 8-A
Attack Potency: Multi-City Block Level
Speed: Relativistic
Durability: Unknown

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