I typically load rviz with config files i.e.:

<node pkg="rviz" type="rviz" name="rviz" args="-d $(find my_pkg)/cfg/viz/overlay.rviz"/>

This also saves frames in there...however, when I have changed a frame name in the launch file, rviz complains that the frame save in the config file frame [...] does not exist. Currently, I am manually adapting the names to the new name in the config file. But there must be a cleverer way to do that, right? Thx!