[ezodagrom]

It's not the same, some things are disabled on non-steam games, like the amount of time played.
Most likely I'll just open the expansion through the Steam library, I guess.

EDIT: I decided to try asking Steam support, to know if it's possible to create a shortcut from the expansion.
Until I get a reply, I figured out a way to trick Steam, I renamed age3.exe to something else (like age3_backup.exe), then I copied age3y.exe and renamed the copy to age3.exe.
Now, when opening the shortcut that was created by Steam, it opens Asian Dynasties. :P