Sheba, there's a difference between faking an accent and singing a song in dialect. "Annie Laurie" (at least the line you quote) is an example of Scottish dialect). It should be sung as written. There's no good reason to convert it to modern English. If you are singing a somg in a foreign (to you) language, it's important to pronounce the words properly. If it's written in a dialect, sing it as it was written. It's what the author intended. If you're singing "Whiskey in the Jar," or any such songs, sing them in your own accent or risk sounding like a "wannabe." This way you can be true to yourself and the music you're performing, which is an invaluable thing in the world of folk music. Cheers!