Is there a way of editing texts in lines such as font size, type, or erase background?
The size and type can be edited in Engrave Mode/ Font Styles / Horizontal (or Vertical) Line Font. Erase background is available in the bottom panel in Engrave Mode.
Thanks! Does this mean that font size and type has to be edited on a per-project layout?
As far as I know, changes to Font Styles are only saved with projects, not on a global basis - so yes.
If you know you’re going to be changing it (and a bunch of other stuff - e.g. Layout / Master Page / Playback changes) every time, you can always save a file where everything’s set up the way you want it and use that as a template for your projects.
It’s worth saying that you can also use any font style for a line annotation if you create your own text-based line annotations using Engrave > Line Annotations.