Hi Markus01,
Welcome to the forums
There is a way to apply the same export settings to all slices, using the 'copy & paste' function of the slices panel. I've attached a quick video below showing this!
2019-09-12 14-57-25.mp4
Unfortunately there's no way to do this from the File>New dialog currently, however you can add new artboards using the artboard tool, which will add the artboard with equal spacing between each. This only works in rows however, not columns -
