Hello Morten,
If I understand the issue correctly, you are referring to a MAC Virtual Machine Boot options, is that correct. If Yes, then here is the solution.
While the VM is in powered off state you can edit the settings and move to Options tab, in there in Advanced you will find the Boot Options.
Select the Boot Options and on the right side pane you can see the options to set the boot delay proess.
In Power On Boot Delay set your time for the delay in milliseconds, i.e., if you want a 2 second boot delay you need to enter the value as 200, and 500 for 5 seconds boot delay.
Please revert with any questions, I an herein adding my Contact details below.
email: kvamsi.k143@gmail.com
Phone: +91-970-443-3304.
Regards,
Vamsi.