Holding multiple data types, is Struct the best option?

[kamrann]

USTRUCT(BlueprintType)
struct FTransitionData
{
  GENERATED_BODY()

  UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Menu TransitionData")
  float OpacityB;
};

Note the ‘F’ prefix on the struct name. This is required for all USTRUCTs by Unreal’s reflection system (or anyway was until recently and I don’t think has changed).