This is obviously a bit pedantic but technically she was already impeached. This article is about her being convicted in the impeachment trial. The post title also doesn't match with the article title which more correctly states that she's been ousted.
But the way impeachment process works in SK, once the process begins, you are no longer able to function as president.
So 'effectively', she was already impeached.
Obviously I'm the one being pedantic. lol.