ChartJS – adding scroll to horizontal legend in Line chart

I would like to know, if there is a way to scroll through the
x-variables,

You can use .removeData( ) to remove the (current) first set of points. This would keep only the same number of (latest) points visible on the graph.

…and always have set distance between the points?

Unless you remove points maintain a set distance while adding points would cause the graph width to increase – which is usually not what you want to do.