using the Meta specifiers on the UClass defenition and at the UProperty, it looks like this which is like using a Struct but with the actual Class selectable:
UCLASS( BlueprintType, Blueprintable, DefaultToInstanced, EditInlineNew )
class SPACENEBULASTARFIELDV3_API UEigenMatrix : public UObject
{
GENERATED_BODY()
public:
UPROPERTY( EditAnywhere, BlueprintReadWrite, Category = "Player Variables" )
int32 rows = 1;
UPROPERTY( EditAnywhere, BlueprintReadWrite, Category = "Player Variables" )
int32 columns = 1;
FMatrix matrix;
};
UCLASS()
class SPACENEBULASTARFIELDV3_API ATestActor : public AActor
{
GENERATED_BODY()
public:
UPROPERTY( Instanced, EditAnywhere, BlueprintReadWrite, Category = "Player Variables" )
UEigenMatrix* NewVar0;
};