About a year ago I made a post on the same subject: ArcGIS Pro Create Locator fails; I followed up with Bug Fix with Create Locator Tool describing a bug that would be fixed at 2.5; I'm using pro 2.5.1 and I'm getting the same error I did a year ago:
Error happened while transforming data
Failed to execute (CreateLocator).
This time it's with centerlines on a local file geodatabase; I ran the repair geometry tool and it reported it deleted one null geometry but I still get the failure. Just for fun I ran the check geometry tool and it found no problems.
So if this bug was fixed (?) and there is no problem with the geometries, what is causing my Create Locator to fail?
here is the dope on my centerlines: