Thanks, really appreciate it, but what Should I be setting as the type for the new outputs?
using auto also fails! :
auto output_o = onet.forward(inputs);
auto output_p = pnet.forward(output_o);

while I expected this to work!
also these failed as well :
std::vector<c10::IValue, std::allocator<c10::IValue>> output_o = onet.forward(inputs);
std::vector<c10::IValue, std::allocator<c10::IValue>> output_p = pnet.forward(output_o);

and also this :
std::vector<c10::IValue> output_o = onet.forward(inputs);
std::vector<c10::IValue>  output_p = pnet.forward(output_o);

results in :
Severity	Code	Description	Project	File	Line	Suppression State
Error	C2440	'initializing': cannot convert from 'c10::IValue' to 'std::vector<c10::IValue,std::allocator<c10::IValue>>'	LibtorchPort	G:\Codes\cpp\port\LibtorchPort\LibtorchPort\LibtorchPort.cpp	52	
Error	C2440	'initializing': cannot convert from 'c10::IValue' to 'std::vector<c10::IValue,std::allocator<c10::IValue>>'	LibtorchPort	G:\Codes\cpp\port\LibtorchPort\LibtorchPort\LibtorchPort.cpp	53	


and also this:
torch::jit::IValue output_o = onet.forward(inputs);
torch::jit::IValue output_p = pnet.forward(output_o);

results in :
Severity	Code	Description	Project	File	Line	Suppression State
Error	C2664	'c10::IValue torch::jit::Module::forward(std::vector<c10::IValue,std::allocator<c10::IValue>>)': cannot convert argument 1 from 'c10::IValue' to 'std::vector<c10::IValue,std::allocator<c10::IValue>>'	LibtorchPort	G:\Codes\cpp\port\LibtorchPort\LibtorchPort\LibtorchPort.cpp	53	
Error	C2664	'c10::IValue torch::jit::Module::forward(std::vector<c10::IValue,std::allocator<c10::IValue>>)': cannot convert argument 1 from 'c10::IValue' to 'std::vector<c10::IValue,std::allocator<c10::IValue>>'	LibtorchPort	G:\Codes\cpp\port\LibtorchPort\LibtorchPort\LibtorchPort.cpp	54	


and
std::vector<torch::jit::IValue> output_o = onet.forward(inputs);
std::vector<torch::jit::IValue> output_p = pnet.forward(output_o);

results in :
Severity	Code	Description	Project	File	Line	Suppression State
Error	C2440	'initializing': cannot convert from 'c10::IValue' to 'std::vector<c10::IValue,std::allocator<c10::IValue>>'	LibtorchPort	G:\Codes\cpp\port\LibtorchPort\LibtorchPort\LibtorchPort.cpp	52	

Severity	Code	Description	Project	File	Line	Suppression State
Error	C2440	'initializing': cannot convert from 'c10::IValue' to 'std::vector<c10::IValue,std::allocator<c10::IValue>>'	LibtorchPort	G:\Codes\cpp\port\LibtorchPort\LibtorchPort\LibtorchPort.cpp	53