For these effects, you must choose a Monospaced font and both "sides" must have the same number of characters.
As it's a blend effect, the colors of the banners have to be white or black.
To edit the text, it's super trouble (because both Text element are over each other).
So the best and faster way to do it, is to select and move the element:
Drag and drop it outside his section. So you can easily edit the text. Then you move it back to his original position.
Note that it doesn't look great on mobile (for obvious reason).