https://sneakemail.com (or https://snkmail.com) is something that I use for more than 10 years, I am very happy with it. Allows newsite-mytag@snkmail.com as well as generating completely looking-random addresses. I wish they would have an app, but works as is perfectly fine for me and my family (when they are willing to use it...)
I want something like mailhero combined with a paid email provider like proton mail. Everything sent to $name@$spamkey.$mydomain.$tld would act like a mailhero address and forward to my personal address.
See https://news.ycombinator.com/item?id=11781361 or https://mailhero.io/