One way to offset dimple's tick labels at the mid of each interval is to use dimple.axis.shapes after the plot has been drawn. This allows to access each SVG <text>
element (i.e. the labels) that can be translated using raw d3 capabilities (see https://d3js.org/d3-axis).
Here's how one can move each tick label 55 pixels to the right and 5 pixels upwards:
myLinePlot.draw();
x.shapes.selectAll("text").attr("transform", `translate(55,-5)`);