On ESXi 7.0, you can import a custom certificate and key.
SCP the PEM format certificate certificate.crt to esxiserver:/etc/vmware/ssl/SCP the PEM format private key private.key to esxiserver:/etc/vmware/ssl/cp /etc/vmware/ssl/rui.crt /etc/vmware/ssl/rui.crt.backupcp /etc/vmware/ssl/rui.key /etc/vmware/ssl/rui.key.backupcp /etc/vmware/ssl/certificate.crt /etc/vmware/ssl/rui.crtcp /etc/vmware/ssl/private.key /etc/vmware/ssl/rui.keyservices.sh restart.