Here is a copy of the SSDT-UIAC-A2AF-Z270X-Designare.aml I created for your Z270X-Designare system. I have also attached an SSDT-EC.aml which will need to be used alongside the SSDT-UIAC.
To install these SSDT's you need to mount your macOS drive, use Clover Configurator.

Open Clover Configurator - this is the Home screen with nothing selected.

Navigate to the 'Mount EFI' tab below the 'Tools' heading in the left hand navigation bar

Select the 'Mount Partition' button next to your macOS drive.
In my case this is the APFS Container [Mojave, Preboot, Recovery, VM]. Now when the System control window pops up you need to enter your password.
This action will allow Clover Configurator to mount the hidden 'EFI partition'.
An new Hard Drive icon will appear on your desktop, named 'EFI'.

Select the 'Open Partition' button in Clover Configurator.

This will open the EFI Partiton/HD icon. This screenshot shows the contents of my EFI partition.
Open the 'EFI' folder.

This screenshot shows the contents of my EFI folder.
Open the 'CLOVER' folder.

This screenshot shows the contents of a standard CLOVER folder, using Clover_v2.5k_r5099.
Open the 'ACPI' folder.

This screenshot show the contents of a standard ACPI folder, with three sub-folders.
Open the 'patched' folder.

This screenshot shows the the contents of my 'patched' folder.
Yours will be empty or may possibly contain the SSDT-XOSI.aml.
This is the location where you need to copy the two SSDT's. /EFI/CLOVER/ACPI/patched folder.
I usually drop the leading /EFI designation when writing locations in any posts in the forum, so I wold write /CLOVER/ACPI/patched.
Hope that helps.