Hi @leo_wong
LPC1778FET180 is an older LPC17xx device and is not supported by the modern MCUXpresso SDK Builder.
You can import it from file system.
Harry_Zhang_0-1782785965987.png
Harry_Zhang_1-1782785985817.png
The absence of a .mex file and graphical Pins/Clocks configuration is expected. These MCUXpresso Config Tools features are primarily available for devices that have MCUXpresso SDK support. LPC1778 projects generally require manual pin and clock configuration or the use of LPCOpen APIs.
BR
Harry