Just do it manually.

You absolutely can set an alarm for a specific day in google clock version 7.6 from the play store.

After you set the alarm if you click on it you can give it a name such as "laundry" and set it for a specific day such as "Sunday"

I have alarms for workdays and alarms for times to take medicine.

You can set an alarm for a early wake up for a flight time a week ahead of time if you want. The assist is super basic to protect you from doing dumb shit, but you absolutely can do it manually.