SCVMM 2019 SDN deployment

Hi,

I have questions with regard to deployment of SDN 2019 in SCVMM 2019.

a. For SCVMM 2019 deployment of SDN, does it still require the 3 networks namely Management, HNV and transit as before? Github templates is still using the old templates. Not sure whether it is still valid. 

b. If SDNExpress 2019 is deploy first and then SCVMM 2019 is installed, is it able to manage SDN? Notice that SDNExpress 2019 only use Management and HNV network.

Thanks