How you add XXHDPI and XXXHDPI Android icons?

Looking at Googles documentation, and my phone, it seems that there are higher tiers of icon resolution than what is exposed in project settings.

[https://developer.android.com/guide/practices/ui_guidelines/icon_design_launcher.html#size][1]

How would one go about supporting those higher icon resolutions, are they added using some different method?

Another bump for this one!

No solution or progress on this? Is it not a bit weird to have a product with one of the main sales points being graphic fidelity represented by a, in comparison to neighboring icons, blurry mess?
The existence of the higher res icons are not a secret: Android launch icon guidelines

Trying to add the higher res icons to the APK manually is arduous and seems silly with the other so nicely integrated in Android project settings. One would assume it would not be too massive a task to add support for the two remaining icon sizes? I believe it would be a boost for product reception on high res Android devices, presumably a target for the engine now and in the future.

Looking at how to add splash screens in different resolutions, I gave the method a shoot with Icons.
I added the intended xxxhdpi icon bitmap file to the [projectname]\Build\Android\res\drawable-xxxhdpi path. Build the project to Android successfully. Opened the resulting APK file, and confirmed that both the xxhdpi and xxxhdpi icons were now present in the APK file. However this did not result in them being utilized when the APK was installed on test devices.

I’m again at a loss at how to make the higher resolution icons work on Android. Any thoughts or suggestions in relation to this problem would be appreciated.

From 4.17 the method of adding the higher resolution icon files as [projectname]\Build\Android\res\drawable-xxhdpi\icon.png and [projectname]\Build\Android\res\drawable-xxxhdpi\icon.png respectively, actually works.

Being able to add them via the project properties would still be a bit more practical, but it is at least possible to include them.

Works indeed, I work in 4.22.3.
Thank you for your answer!
Strange that after 5 versions the option XXHDPI and XXXHDPI is still not available in project settings.