Quick answer: Unreal Blueprint Set Color on a material property not visible at runtime? Mesh uses the shared material; set on the instance via SetDynamicMaterialInstance.

Set tint via Blueprint; tint doesn't change.

Use dynamic material instance

MID = Mesh->CreateDynamicMaterialInstance(0);
MID->SetVectorParameterValue("Tint", color);

Per-instance changes; doesn't affect shared.

Or use material parameter collection

Global parameters; affect all materials simultaneously. Different use case.

Audit material set patterns

Each material edit: shared or instance?

“Material edits need the right primitive. Shared vs instance.”

Document the dynamic material instance pattern. New contributors discover the silent failure mode otherwise.

Related reading