I want to set default settings for the checkboxes in the Asset Options section of my HDA. Can anyone help? e.g. I want to always turn on "Do Not Generate Outputs".

would like to know this as well if you've came across a solution

Hi,

Please see https://www.sidefx.com/docs/houdini/unreal/attributes.html#generic

Generic attributes can be applied to the HDA itself, if the attribute is set as a detail attribute.

To get the list of attributes that can apply to a given class, type the following CMD in Unreal:

Houdini.DumpGenericAttribute XXX

XXX being the name of the class, in your case, you'll type

Houdini.DumpGenericAttribute UHoudiniAssetComponent

Which will list all properties that can be modified on a HoudiniAssetComponent, you'll be interested in:
unreal_uproperty_bOutputless : bOutputless (Outputless) - UE TYPE: BoolProperty - H TYPE: int.

so to automatically change the "Do Not Generate Outputs" toggle, you want to create the detail attribute "unreal_uproperty_bOutputless" and set its value to 1.