But it does allow you apply an effect for example: a bevel and emboss (part of layerfx.py) and save that as a preset name by calling "Apply and Save Preset Bevel and Emboss".
Then later you can apply a preset by calling "Load Preset Bevel and Emboss" and choosing the preset name you've previously saved.
Also version 7 and up allows you to apply all layer effects presets with the same name.
For example if you have saved a preset bevel and emboss called "candle" and an inner shadow called "candle" (same name) you can apply both in one go by calling "Load Preset Apply All" and choosing "candle".
See also Layer Effects Presets Collection for presets to be used with this plug-in/script. Plug-in Menu locations:
multiple entries under
Layer/Layer Effects
for example for Bevel and Emboss it's under
Layer/Layer Effects/Apply and Save Preset Bevel and Emboss
Layer/Layer Effects/Load Preset Bevel and Emboss
Settings files are saved as .txt files under the working folder (wherever you execute GIMP from).
For example, for bevel and emboss settings it's saved under "bevel_and_emboss.txt".
They're just text file that has each setting on a line starting with preset name followed by the pipe (|) character then followed by parameters used. So if you wanted to share these settings you can by just copying whatever lines you like to corresponding .txt file or rename the preset name by just changing the text in front of the pipe.