Long story short
We have a coexistence of 2016 and 2019 (2+2 Servers each)
We were in the last stages of doing the cutover for Firewall changes for Receive connector,Mail routing, autodiscover internal and we discovered that Webservicesvirtualdirectory takes ages (more than 20minutes) to pull the information from all servers.
We have 2 sites (A & B).
Site A = Exchange 2019 + Exchange 2016
Site B = Exchange 2019 + Exchange 2016
Now matter from which server we try, the results from PS - Get-Webservicesvirtualdirectory
Searched all over the internet and could only find below information which just talks about a workaround and no root cause or resolution. Please help anyone !!