If you want to make an Imperial character then you have to buy the Imperial edition - there's no other way to get access to the race.
(Just make sure you buy the Imperial Edition upgrade and not the Imperial City DLC - I know some people get them confused but they are completely different - the Imperial City does not allow you to make Imperial characters.)
PC EU player. | PAWS (Positively Against Wrip-off Stuff) - Say No to Crown Crates!
"Remember in this game we call life that no one said it's fair"