I imagine you know this already, but hey.com has this as a key feature. I've even seen an article or two about how to get Fastmail to do something similar, whi

I imagine you know this already, but hey.com has this as a key feature. I've even seen an article or two about how to get Fastmail to do something similar, which I imagine would work for Gmail too, e.g. https://www.joshuawood.net/make-fastmail-work-like-hey https://www.joshuawood.net/make-fastmail-work-like-hey