I'd recommend that you:
1) shutdown the VM
2) go to VM settings, remove old NIC(s) and add the VMXNET 3 adapter
3) start the VM
If you have DHCP then the VM should get the IP addr automatically. In case of static IP addr you will probably need to re-configure the settings (appliance - netconfig command).
Note: if you have agents, they have to point to correct IP address (or better to use hostname of LEM Manager)