How to migrate a qubes system to another laptop?

[apparatus]

You can, but you’ll need to fix the PCI devices passthrough to your qubes:

@apparatus

Qubes OS is attaching PCI devices to the qubes (e.g. sys-net/sys-usb) based on their BDF and they may be different on another computers. And the available devices may be different as well.
For example, you have PCI Network Controller with BDF 03:00.0 attached to your sys-net in your computer, but on another computer the device with BDF 03:00.0 could be the GPU and the GPU will be attached to sys-net instead of dom0 so your Qubes OS will boot with black screen or won’t boot at all.
Or there could be only one USB controller on another computer so you won’t be able to use sys-usb there.

You can boot the Qubes OS without qubes autostart like this:

Autostart troubleshooting | Qubes OS

And also remove the rd.qubes.hide_pci from the kernel command line options in GRUB so it won’t hide e.g. GPU from dom0.
Then you can configure the PCI devices attached to your qubes (sys-net, sys-usb) and specify correct USB controller to hide from dom0 using rd.qubes.hide_pci option.
Then you can use this Qubes OS on another PC.