is it required to press any key after restarting a virtual controller on VM console?
If yes, is there an option to automating this process so that the controller starts without pressing a key.
No need to press any key for vWLC reboot.
Please go through the below deployment guide for vWLC boot process.
The VWLC should always complete the boot process without any intervention. You only have to press a key if you want to use the "VMware console window" as a controller console window.
You can redeploy the VWLC and If problem still persist please contact TAC (firstname.lastname@example.org)