Yes, please. This.

Any updates on this? (sorry to bump)

Wow, disappointing this request is almost 4-years old and still not implemented. Exact same problem, and the regex ability is brilliant, but then falls flat on it's feet in automation because you can't set the default Display Name. It's a core part of basic email, especially to avoid getting it marked as spam, so I am surprised the team missed this. But mostly surprised that it's gone this long on deaf ears. Hopefully someone drops back by simplelogin someday for some updates.

SimpleLogin deserves Simple Rules. Auto Create Alias Rules need to have a box to specify the Default Display Name for each match.

For those still looking for a solution, addy.io does this perfectly with the "rules" feature. For any domain, you can set a rule that if any reply comes from your true mailbox address (realaddress@proton.me for example), it adds whatever "From Name" you want to your alias when your recipient sees. Pure genius implementation, and a great solution that can be implemented on any regex match you want!

I've been evaluating both simplelogin and addy.io, and not only does this solve this basic alias management requirement for new aliases, addy also is getting regular updates including a modern Android app. SimpleLogin could easily fix this as shown in the image below.

Simple fix: