Quoting Daniel Hornung <daniel.horn...@gmx.de>:
> Or you could try
> and write a script that changes the text of all text layers in the same way,
> I think that should be possible at least in theory.
Yes, such is possible (and owing to recent additions to the Procedural
DataBase, not just in theory).
The following Script-fu will add a new command to the Layers Menu
(accessible by right-clicking on a thumbnail preview in the Layers
Dialog). The command is called "Clone text attributes..." and presents
a list of several attributes from which the user can choose to
transfer to the target layers. Target layers can be limited to visible
layers, linked layers, or all layers (only text layers are affected).
Gimp-user mailing list