I was checking out a cached version of Lazytown.com from 2003 and found the below image of a shoeline that was put out. If you look closely, you will see that the character's names are listed on the shoe box.
You will see that there is Solla Stira/Stiffanie (Stephanie), ═■rˇttaßlfurinn (Sportacus), Goggi Mega (Pixel), and unless you can read it better than I can, they have the name Toemy (pronounced like Tommy) next to Trixie. It seems as if for a little while they planned to name Trixie that. I guess they were going for a tomboy thing.