I redesigned IMX8MMEVKHUG and removed :
Ethernet PHY
QSPI Nor Flash
SD card
PCIe Gen.
Will the device be able to boot?
Do I need to make changes in the device tree?
You boot up you board from emmc? Yes, it can work. And if you do not change the device tree it can also can boot up, but you'd better to disable the section you move in device tree.