Lemmy

Not on your side, I think. The @ (at) notation is pretty standard for email where you have "prefix@postfix.domain".

If the poster cares enough (or simply remembers), they can properly format the link to look like a simple @ notation, but with a full link to the community they're referring to inside. Like this: gaming@beehaw.org.

Maybe there's a way to do it automatically, but I'm not sure if there's a good way to achieve this, without putting too much stress on the instance. The reason you'll probably have to parse the string to see if the postfix is an actual instance (which can be plentiful, that's already some computing power) or something unrelated, then automatically converting the traditionally email link to a regular one (which isn't that hard, I think, as you already have the instance URL and the community name).

Perhaps a slightly better way would be to only parse links that start with an exclamation mark, similarly to what one can see in the community sidebar when visiting it from another instance: like !gaming@beehaw.org.

But I am, of course, kinda too lazy to try and implemented that, even though that could be a fun way to learn something and get something to show off during my career at the same time.