First create a brand new BP from AQTBDWeaponProjectile and try again. Sometimes hot-reload messes up BP and lost reference to components.
Secondly I’d suggest change EditAnywhere to VisibleAnywhere here:
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Movement)
class UProjectileMovementComponent* WeaponProjectileMovementComponent;
For components, EditAnywhere means you expect it to be reassigned with a different component. While in this case you just want to modify the properties. In my experience EditAnywhere also make the UI in Detail tab quite confusing.