Grisha Yeager vs Po (Kung Fu Panda): who would win?

Po (Kung Fu Panda) favored — Slight edge (~55%)

Grisha Yeager · Attack on Titan · Titan Form

Tier
8-B
Attack Potency
City Block Level+
Speed
Subsonic, up to Supersonic
Durability
Building Level

Po (Kung Fu Panda) · Kung Fu Panda · Kung Fu Panda 4

Tier
8-B, up to 7-C
Attack Potency
City Block Level, up to Town Level
Speed
Supersonic+
Durability
City Block Level, up to Town Level

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