i dont think P2V over the WAN will be nice idea.
Nope, it is not, besides Converter needs direct connectivity from the physical source to the target ESX box.
Can we Convert the physical machine into virtual machine with the help of VMware Workstation converter and than ship the Vdisk to central DC and than import into VMware Environemnt.
Yes, if your physical source is Windows. For Linux physical sources you cannot create a Workstation image, but you need to convert it to an ESX. However after performing Linux P2V to an ESX box, then you can perform V2V conversion of the result to a Workstation image and import it back on the target site.