Rotating the pivot point only

is there a way to rotate the pivot point (or the local transformation orientation if you prefer) of an object without affecting the geometry?

Sure, i could rotate the object, then rotate only the geometry in edit mode back the same amount but that is rather time consuming if you have to do it for multiple objects. Other programs have buttons where you can set transformations and rotations and scales to only influence the pivot. Is this possible in Blender?

there is this addon

Awesome. Thank you.

You can also add a new object, orient, scale, and position it correctly, and then “join” the old geometry into the new object (CTRL-J).
If you want some old geometry as reference, make a copy (SHIFT-D) and seperate it §. Then you can exit edit mode, re-orient the reference geometry, and then join the old object into the reference. This second method has the advantage of maintaining all modifiers and hierarchy location.